Is Bud Norris' Newfound Success Sustainable?

Norris has been fantastic after starting the year horribly. Which pitcher will the Dodgers be getting?

"Adapt or perish." This phrase was used by the science fiction author H.G. Wells, and while he wasn't referring to anything baseball-related, it's nonetheless applicable to the sport.

Case in point, new Los Angeles Dodgers pitcher Bud Norris.

The Dodgers acquired him Thursday in a trade with the Atlanta Braves, and while we won't really discuss the deal, we will examine what type of pitcher the Dodgers will be getting.

A Tale of Two Pitchers

Norris began the year in Atlanta's starting rotation, making five starts in April but pitched poorly enough to be demoted to the bullpen. He made 12 appearances in relief (18 1/3 innings) and posted a 1.96 ERA, which earned him a spot back in the starting rotation.

Since rejoining the rotation, Norris has made another five starts, and the results have been completely different from what they were at the beginning of the season.

Point in Season IP HR ERA xFIP BB% K%
First 5 Starts 22 2/3 6 8.74 5.32 15.0 9.7
Next 5 Starts 29 1/3 0 2.15 2.85 7.0 18.3

His ERA dropped 6.59 points, his Expected Fielder Independent Pitching (xFIP) fell 2.47 points, and his walk percentage was more than cut in half, while his strikeout percentage almost doubled.

Is Norris' success tied to a decision to adapt, or are hitters just finding less luck as of late?

Simply put, Norris adapted in a big way. He made a significant change to his arsenal of pitches, and it's made a world of difference. Check out his pitch selection (via Brooks Baseball) across his first five starts versus his next five.

Point in Season Fastball Slider Sinker Changeup Cutter
First 5 Starts 54.95% 26.18% 11.08% 7.78% N/A
Next 5 Starts 45.07% 30.82% 6.92% 0.42% 16.77%

What should jump out immediately is that Norris has started throwing a cutter and basically stopped throwing his changeup. We know that his ERA and xFIP have seen major drops, but are they due to legitimate reasons?

It certainly looks that way. Here's another table to help explain.

Point in Season GB% Hard% O-Swing% SwStr% fWAR
First 5 Starts 44.0 31.8 25.3 6.5 -0.4
Next 5 Starts 59.2 26.9 33.3 10.9 1.1

Over his last five starts, Norris is inducing ground balls (GB%) at an astounding rate, while reducing the percentage of hard-hit balls allowed (Hard%). His totals in these two categories over his last five starts would rank first and 12th-lowest among qualified starters this season.

Norris has also increased both the amount that hitters are swinging at pitches outside of the strike zone (O-Swing%), and his overall swinging strike percentage (SwStr%). These marks would rank 10th- and 24th-best among qualified starters this season, respectively.

The end result is going from a Wins Above Replacement (fWAR) in April of -0.4, which was worst among starting pitchers with at least 20 innings pitched, to a 1.1 fWAR in June, which is ninth-best and better than Jon Lester, Noah Syndergaard, Cole Hamels, and Jake Arrieta just to name a few.

This isn't to say that Norris is all of a sudden better than the studs just listed, but it does mean that his recent impressive streak is worth paying attention to. He made a lot of New York Mets hitters look foolish in his last start, which came on Sunday.

Norris in Los Angeles

Exactly which type of pitcher the Dodgers are getting is tough to say, especially considering the small sample sizes of when Norris struggled and his subsequent resurgence. He'll likely return to an xFIP that is closer to his career average of 4.04, which is better than the current league average (4.21 xFIP).

With basically their entire rotation on the disabled list, the Dodgers don't need Norris to be an ace and rather will hope he can be a stop-gap until his fellow pitchers get healthy. And if hitters begin adjusting to his new pitch repertoire, Norris will just have to adapt once again.

It's either that or perish.