Bud Norris: More of a risk than we realize for the Orioles?

In a trade deadline that lacked any sort of excitement overall (no surprise given the limited handful of players available), the Baltimore Orioles made one of the only significant moves of the day, acquiring starter Bud Norris from the Houston Astros.

On the whole, in a more general sense, this looks like a deal that would favor the Orioles. They get a proven starter -- who's under team control until 2015 -- in exchange for a fringe guy in L.J. Hoes and Single-A pitcher Josh Hader. Simple enough right? Not so much.

As Eno Sarris over at FanGraphs points out, there's actually some risk (potentially significant) in acquiring Norris, when looking deeper. On the outside, his numbers are solid. He's a front-end starter, boasting a 3.93 ERA and a 3.87 FIP. A look deeper, though, and it isn't too difficult to see why this deal could be looked at as a risky one.

The first thing that Sarris does is to point out his strikeout rate, which is declining thanks to his velocity, which has also made its way down a touch:

Even focusing just on his strikeout rate, Norris is already in decline. In 2010, he threw 93.6 mph and struck out 23.1% of the batters he faced. This year, he's down to 92.4 and 16.6% respectively. From what we know about pitcher aging curves, his velocity loss fits the pattern.

(Here are the pitcher aging curves, for your viewing pleasure.)

That's the first warning sign when looking at Norris. But there's also the matter of his performance against lefties, which is shoddy at best. In fact, he's had a really rough go of it against lefties this season. He's fared well against right-handed hitters, holding them to a .240 average for the year and 52 of his 90 punchouts coming against the righties.

He's tried mixing up his arsenal when it comes to facing lefties, but even that hasn't led to a great deal of success: He does have a changeup, and he throws it to lefties. Last year, he threw it around 10% of the time to lefties, and this year, it's more like 18%. He knows about the slider, and platoon splits, so he's giving it a go. Too bad, because now his strikeout rate against lefties has tanked (20.1% career, 12.5% this year), and he's giving up even more home runs to lefties. The changeup gets about half of the whiffs of a league average changeup.

The long and short of it here is that Norris doesn't miss a lot of bats. Combine that with his struggles against lefties, and there's certainly a bit of a cause for concern. Eno went on to raise one more intriguing point about Norris and his role with the Orioles:

Bud Norris has a reliever's arsenal, and even if he is projected to be slightly better than the man he may replace in the rotation - Jason Hammel - he would be an iffy start against a lefty-heavy team in September. In October, he's more likely to move to the bullpen than anyone else in that rotation.

That will be a situation to watch come September and October, especially after Hammel returns. Regardless of how that plays out, both for the remainder of the year and heading into next season, it's important to keep the Norris acquisition in perspective.

The O's know they weren't acquiring Cliff Lee. They managed to surrender very little, while acquiring an arm that will add depth to their rotation, which gives them one of the deeper groups of any American League contender. Now if the Orioles had brought Norris to headline their rotation, or slot in as a No. 2 guy, they could be in some trouble, given his alarming splits.

But this is a case of acquiring a proven arm to add to the back of the rotation. The Orioles did that successfully in acquiring Bud Norris. As for a future in the bullpen, if his velocity continues to decline and his repertoire continues to be somewhat unreliable, the O's are hoping they can hold off on that decision until the 2014 season.

. . .

All statistics courtesy of FanGraphs.

Randy Holt is a writer at Beyond The Box Score. You can follow him on Twitter at @RandallPnkFloyd.

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