The Detroit Tigers acquired Daniel Norris at the 2015 MLB trade deadline and instantly inserted him into the starting rotation, despite the Blue Jays having kept Norris in Triple-A Buffalo for the majority of the season. The move might have said more about the Tigers’ current situation than Norris’, as Detroit’s season was essentially over by early August. After a dazzling debut that went 7 1/3 innings, the whole organization was excited about the prospect's bright future.
But after multiple injuries and a cancer scare within the last year, Norris has struggled to match the performance of his very first start. Norris has made 14 starts in a Tigers uniform and has pitched only 65 total innings. His stats in this limited number of outings have not been bad for a young pitcher; Norris owns a 3.74 ERA, 4.40 FIP, and 1.32 WHIP with 7.06 strikeouts per nine innings and 2.49 walks per nine.
However, one area does stick out: Norris has had a difficult time pitching deeper into games.
Between 2015 and 2016, Norris is averaging just over 4.5 innings per start. This is more than an inning shorter than the rest of the Tigers starters in 2016 and about 1.5 innings less than qualified MLB starters have averaged this season. He has thrown slightly more pitches per inning than his peers and has a lower strike rate, but these do not seem significant enough to be the root of the issue. To dive a bit deeper, we look at each of Norris’ 14 starts with Detroit.
Joining the Tigers
8/2/15 - 7.1 IP, 84 P, 4 H, 1 ER. Summary: good start
8/7/15 - 3.1 IP, 83 P, 9 H, 5 ER. Summary: bad start
8/12/15 - 6.1 IP, 96 P, 6 H, 4 R (3 ER). Summary: adequate start
8/19/15 - 4.1 IP, 81 P, 4 H, 3 ER. Summary: adequate start, injured mid-game
Return from oblique strain
9/16/15 - 3.2 IP, 47 P, 1 H, 1 ER. Summary: good start, pitch limit
9/22/15 - 5.0 IP, 63 P, 0 H, 0 ER. Summary: good start, pitch limit
9/29/15 - 1.2 IP, 71 P, 5 H, 6 R (2 ER). Summary: bad start, but fault of the defense
10/4/15 - 5.0 IP, 71 P, 1 H, 0 ER. Summary: good start
Return from lower back issue
6/23/16 - 5.0 IP, 79 P, 6 H, 3 ER. Summary: adequate start
6/29/16 - 5.0 IP, 100 P, 8 H, 2 ER. Summary: good start
7/4/16 - 2.0 IP, 31 P, 3 H, 2 ER. Summary: adequate start, injured mid-start again
Return from oblique strain
8/9/16 - 5.0 IP, 85 P, 7 H, 1 ER. Summary: good start, removed with bases loaded
8/15/16 - 5.1 IP, 88 P, 6 H, 2 R (1 ER). Summary: good start, removed with two men on
8/20/16 - 5.0 IP, 84 P, 8 H, 3 ER. Summary: adequate start, removed after rain delay
Clearly some of Norris’ starts have been affected by situations beyond his control. Twice he was removed from the game with an injury, a couple of times he was on a limited pitch count, and his most recent outing was shortened by rain. But even removing these five starts (italicized above) still does not solve the whole problem. The remaining nine outings yield 4.89 innings per start, 84.1 pitches per start, and 17.2 pitches per inning, numbers that are better than his overall totals but still below average.
In reality, Norris' low innings-per-start comes from multiple factors. Even when healthy, he does seem to run into some trouble that will cause him to be removed for a reliever after five or so innings. However, Norris has not pitched more than four consecutive starts with the Tigers without suffering some sort of injury, so perhaps he will not encounter this problem once he can actually stay in the rotation for more than a few turns.
At this point there should not be too much cause for alarm, as Norris is still young and clearly has not had much major-league experience. The Tigers have wisely been careful with his innings given his injury history, and he still owns a 3.68 ERA his nine unencumbered starts. Health will be the first thing to watch with Norris as he progresses in his career. Once he can figure that out, the longevity of his starts can be put into greater focus.