With Detroit’s rotation decimated by injuries, the young right-hander is evolving from a depth arm into a bona fide ace through refined sequencing and elite pitch value.
The Tigers, at 19-24 following their second straight loss to the Mets on Wednesday night, turn to Keider Montero on Thursday afternoon at Citi Field.
Montero has been the most consistent starter the Tigers have had this season, and the case can be made that he has been Detroit’s “ace” so far. That is not meant sarcastically. It is more a reflection of where the Tigers are, how thin the rotation has become and how steady Montero has been while the rest of the staff has been hit by injuries.
Granted, the Tigers have Casey Mize, Tarik Skubal, Reese Olson, Troy Melton and Justin Verlander on the injured list. Hinch has mentioned several times that Montero is a starter, and there is a reason for that. Detroit has needed him to be more than a depth arm. The Tigers have needed him to take the ball every fifth day and give them a real chance to win.
So far, he has done that.
Montero entered Thursday’s start against the Mets with a 2-2 record, a 3.18 ERA, 39 2/3 innings, 29 strikeouts and a 0.96 WHIP over seven starts. With an ERA of 1.42 over his last two starts, it has given Detroit one of its few steady rotation pieces going into the series finale in New York.
The surface numbers are strong enough, but the Statcast profile shows why this version of Montero looks different from the one the Tigers saw last season.
His Baseball Savant pitching run value has jumped from the 20th percentile in 2025 to the 89th percentile in 2026. His fastball run value has moved from the 58th percentile to the 86th percentile, while his offspeed run value has gone from the 68th percentile to the 93rd percentile.
That is the starting point of the case. Montero is not just surviving because the Tigers need innings. He is getting better results with the pitches that have to carry him as a starter.
The fastball is probably the best example of the difference.
Montero’s four-seamer averaged 93.9 mph last season. This season, it is at 94.1 mph. So this is not about a major velocity jump. The change is more about when he is using it, how he is setting it up and how the rest of the mix is helping the pitch play.
Last season, hitters produced a .353 wOBA and .378 xwOBA against his four-seamer. This season, those numbers are down to .295 and .320. He is also using the pitch slightly more, going from 30.8% last season to 33.8% this season.
The sequencing is the key part. Montero is not living off the four-seamer by itself. He is pairing it with a sinker that gives hitters a different fastball look, while using the changeup more often and more effectively. His sinker usage has stayed in the same range, moving from 19.9% last season to 21% this season, while his changeup usage has increased from 12.8% to 16%.
That gives him a cleaner fastball/off-speed setup. The four-seamer can work better when hitters have to respect the sinker to a different lane and the changeup off the same general look. For Montero, the fastball improvement is not just about the pitch. It is about how the pitch fits into the plan.
The changeup has been the clearest separator.
Last season, hitters batted .174 with a .257 wOBA and .338 xwOBA against Montero’s changeup. This season, they are hitting .083 with a .075 wOBA and .140 xwOBA against it. The whiff rate on the pitch has also climbed from 21.1% to 29.7%, while the putaway rate has moved from 13.1% to 24.1%.
That gives Montero a pitch he can use to finish at-bats. For a right-handed starter who works with a four-seamer, sinker, slider, changeup and curveball, having that kind of offspeed weapon changes the way hitters have to approach him.
The command improvement is another major part of the jump.
Montero’s walk-rate percentile has gone from 48th last season to 92nd this season. His strikeout percentile has improved from 20th to 28th, which still does not make him an overpowering strikeout arm, but the shape of the profile is much better. He is throwing more strikes, limiting free passes and giving himself more room to work through traffic.
That is the difference between a depth starter and someone a team can trust every fifth day.
There are still some areas to watch. Montero’s hard-hit, barrel and ground-ball numbers are not perfect. His hard-hit percentile has dropped from 59th to 29th, his barrel percentile from 52nd to 24th and his ground-ball percentile from 46th to eighth. Those numbers keep the evaluation honest. He is not dominating every Statcast category, and there is still some contact risk in the profile.
But the expected numbers are moving in the right direction. His xERA percentile has gone from 19th last season to 74th this season. His xBA percentile has improved from 20th to 66th. The overall picture is a pitcher who is doing a better job controlling the zone, mixing his pitches and avoiding the type of damage that hurt him last season.
The third-time-through-the-order numbers also help the starter argument.
In 2025, hitters had a 1.022 OPS against Montero the third time through the order as a starter. This season, that number is down to .660. The sample is smaller, but it lines up with the broader changes in his profile. He is giving Hinch more reason to let him keep working.
That is probably the clearest argument for Montero’s place in the rotation. He has not just taken the ball because the Tigers needed someone to do it. He has pitched well enough to make himself part of the conversation when the rotation gets healthier.
Skubal is still the top arm when healthy. Mize, Olson, Verlander and Melton all change the depth chart when available. Detroit’s injury situation has forced Montero into a larger role, but his performance has kept him there. ESPN listed Skubal and Verlander among Detroit’s injured pitchers, while MLB.com’s injury tracker has also reflected the Tigers’ ongoing rotation issues.
For a Tigers team trying to stay within reach in a winnable division, Montero’s stability has been one of the few clean developments on the pitching side.
He does not need to be called the long-term ace for the point to work. Right now, with the rotation thinned out and the Tigers needing steady innings, Montero has pitched like the arm they can trust.
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