The safest bet
An ankle injury held Adbert Alzolay back this spring so he is still playing catch up. He has taken a no-hitter into the middle innings twice already but has also been bounced relatively early a couple of times in his four starts. Once he is fully stretched out and into mid-season form Alzolay is by far the Cubs best option for any opening in the Major League rotation this summer when factoring in readiness and ceiling.
Improvements: The early returns on the development of his changeup are solid. There were games last year where he would throw the pitch only a handful of times and never in tough situations. The Cubs are forcing the issue this season and Alzolay has shown it can be a very solid, if still inconsistent, offering so far.
Concerns: None, really. They should let him up his pitch count beginning in his next outing so we should start seeing more opportunities to show off his changeup as he works deeper in games.
The rest of the best
We've covered the struggles of Jose Albertos after pretty much every appearance he has made this season, but here's a summation: He's been terrible. Oscar De la Cruz has paired a couple of stinkers with a couple of spectacular outings. Considering all the time he has missed the past few years, consistency is a high bar to set this early in the season. The good news is he looks healthy. Thomas Hatch and Alex Lange have each gotten better after uneven starts.
Improvements: De La Cruz has already pitched half as many innings as he did last year, and shown flashes of his good three pitch mix returning to previous levels. Hatch has remained inconsistent with his control and command but the Cubs are letting him extend deeper into games after handling him with kid gloves in 2017.
Concerns: Where to start with Albertos? His velocity is down a couple of ticks. His control has been abysmal. And the Cubs are asking him to focus on developing his curveball, which means he has yet to feature his best pitch (changeup) this season. I have no doubt mechanical adjustments are being made.
Yet with all that, I remain relatively unconcerned with his on field performance. He is still the highest upside arm the Cubs possess, with the potential for three above-average-to-plus pitches. In fact, I think his changeup is a potential plus-plus pitch. My doubts are the same as during the offseason: Can he remain healthy? How much will he mature, both physically and mentally? Health is not something you can control, you only hope to mitigate the risk. But how much Albertos commits to making himself the best he can be is in his hands.
Every time out Brendon Little finds the strike zone a little more frequently. The issue is he started off the season so poorly that he has only reached "acceptable" levels in his past two games. Hopefully the trend continues though and he can start dialing in his stuff with consistency.
Bullpen help a year away (or less)
Two of the biggest stories among the Cubs pitching prospects last season, along with Alzolay, were the quick ascensions by relievers Dillon Maples and Dakota Mekkes through the Cubs system. Minor League batters proved ineffective against them no matter what level the Cubs pitched them at in 2017, and really the threat to either in most outings was the self-inflicted kind, via walks. The pattern has remained consistent over the first month of this season, but the pair remain very intriguing (yet very different) late inning relief prospects. Maples is still showing the same elite stuff and Mekkes the same elite deception and extension. I believe believe both will receive shots once rosters expand in September, that is if injuries don't open up an opportunity before then.
I've grouped Michael Rucker and Duane Underwood, Jr. in with this pair of relievers, not so much because I have given up on their ability as potential back-of-the-rotation, but because the their development timeline does not coincide with any expected rotation openings. Even if an opportunity does arise, Alzolay is far more likely to receive the first chance to fill such a hole. These two also possess the type of stuff that could play up a bit if deployed out of a bullpen. Both rely heavily on their fastball despite their solid, if unspectacular four-pitch repertoires, so shorter outings could provide a bump in velocity as well as not allowing hitters multiple looks to time them up.
Improvements: Underwood is coming off his first healthy season in a couple of years and it appears he used the experience and the accompanying full offseason to take the necessary next steps in his development. Still just 23-years old, his numbers are improved almost across the board, but most especially in regard to his control. He has cut his walk rate by more than half and has been among the organization's best strike throwers so far this season.
If you can believe it, Maples and Mekkes have actually become more difficult to hit this season than they were in their breakout 2017 seasons. Their batting average against has lowered and their K rates risen. Mekkes will certainly not be able to maintain his utterly ridiculous .080 average against and .129 BABIP, but his ability to prevent hitters from squaring him up should continue to keep both well below league norms. He has has held batters to a well below .200 batting average, and well below .300 BABIP at every stop.
Concerns: It is not a secret that Maples and Mekkes still need to throw more strikes. Both have actually taken a step back in terms of BB%, which isn't a good sign, but neither needs to be perfect given their other strengths. They just need to be better than they've been.
Rucker was one of the organizations premier strike throwers last season and his underlying numbers indicate his 8.6 BB% will not remain so high and should return to normal over a larger sample size.
Long-term BOR or LIR projects
Improvements: Cory Abbott continues to impress me with his control, efficiency, and ability to change speeds. He won't spend all summer in South Bend. His fellow rotation mate, 20-year old Javier Assad has risen to the challenge of full season ball, thanks in large part to a decrease in his walk rate. If he can maintain such a low rate moving forward in his career, Assad greatly improves his odds of fulfilling his back-of-the-rotation potential.
In Myrtle Beach, Matt Swarmer has been the biggest story. Bouncing between four levels after beginning the season as a reliever before getting stretched out, it was difficult to get a good read on him in 2017. He credits his three starts in AA (unsuccessful) and AAA (very successful) last year with helping him identify the type of pitcher he is and attacking hitters with confidence. That has carried over into 2018, posting terrific numbers across the board and cementing himself as a legitimate starter prospect in the org. Expect the 24-year old to return to the upper levels once an opening occurs.
Two more breakouts have occurred as well. Tyson Miller has maintained his solid walk rates while seeing an uptick in velocity and K rates. He didn't miss enough bats last year, but that is beginning to occur as he grows into his frame. Bailey Clark is now healthy, stronger and beginning to find the strike zone with regularity. South Bend proved an insufficient challenge now that he is locked in, and his early results with the Pelicans are encouraging as well.
Trevor Clifton has seen his stuff return close to his 2016 levels. There has still been some inconsistencies though, especially with his command and control. I've never been a huge believer in his ability to remain a starter, but he is at least on the path back to becoming a potential late inning reliever. He was really good his last time out.
Concerns: The first month of the season didn't raise any new concerns so much as provide confirmation that Bryan Hudson is still a long-term project. He is missing a few more bats, which is an excellent sign, but the command still comes and goes. I hold to my belief that Hudson is still at least three to four years away, but the pay off could be really good BOR starter, or even a little more if the 6'8" lefty puts it all together. I'm a believer, but there is still a great deal of risk, and his development will require patience.
I knew the Erich Uelmen as a starter experiment was going to have its ups and downs. Like Hudson he is a long-term project in that regard. There are certainly things to like, especially his GB% and ability to make hitters whiff. But control is still an issue and I remain skeptical regarding his long term ability to retire left handed hitters. The same unorthodox delivery that provides deceptions against righties gives lefties a good look. Without the development of a good change up to combat them Uelmen will become limited to relief, but as a guy with a very good sinker that could be very tough on righties, he has solid upside in that role.
Justin Steele is recovering from Tommy John surgery performed late last summer. While the recovery rate for that surgery has increased dramatically, until we see him on the mound there is still a great deal of risk.
Lower ceiling arms
Improvements: Craig Brooks has taken baby steps in terms of his control so far this season. If he can throw his fastball/slider combo over the plate with more consistency he'll eventually carve out a middle relief role with some team in the Majors.
Keegan Thompson and Duncan Robinson throw plenty of strikes and definitely know how to get Minor League batters out. I just worry their pure stuff remains a bit short to remain effective against big leaguers, especially multiple times through an order. Alec Mills falls into a similar category for me as guys that you would feel okay with giving a chance as the last guy in your bullpen, with the opportunity to earn a larger role later. They'll have to prove it at every level. Tyler Thomas has made enough strides with his control this season for me to envision him similarly down the road.
Concerns: Every concern I have raised regarding Jen-Ho Tseng the past couple of years has come around to bite him this season. His secondaries and command have not been at their best and it has led to him getting absolutely blasted whenever he catches too much plate or has to rely too heavily on his fastball.
Jake Stinnett has not been able to throw strikes consistently enough this season to let his sinker/slider combo play to full effect.
Jose Paulino was a wreck throughout April. He was skipped in the rotation before returning earlier this week, with slightly better results. I've long been skeptical of his chances as a starter, and have been advocating for a move to the pen since the start of last season. I'd like to see the switch made once Erling Moreno and/or Manny Rondon return from injuries suffered this spring, so the org can adequately judge Paulino's utility in that role before he becomes a Minor League free agent this offseason.