Sean O’Sullivan is the 5th starter. Again.   Dick Kaegel over at Royals.com is reporting that the Royals will leave Vin Mazzaro in Omaha after his disaster start and instead use Sean O’Sullivan as the 5th starter this weekend.

What is it about Sean O’Sullivan? He had a couple of season of success as a teenager in the low minors with the Angels and hasn’t been anywhere near as effective since. That’s not a unique story in professional baseball. Plenty of pitchers get exposed when they reach a certain level in the minors. The odd thing about O’Sullivan is that he kept on getting promoted.

He wasn’t a miserable pitcher at the double and triple A levels of the minors, but he wasn’t someone who screamed out that he should be promoted to the Major Leagues at the age of 21. But that’s exactly what the Angels did in 2009. He pitched in 12 games and had an ERA of 5.92. In 2010 he was again brought up to the Major Leagues and put up a 5.49 ERA in 19 games and was traded to the Royals.

In 2010 with the Royals he posted a 6.11 ERA in 14 games. He struck out 37 and walked 27. There wasn’t really anyone beating down the door to join the starting rotation so the Royals just kind of endured Sean O’Sullivan. They really didn’t have much choice.

During the off-season the Royals traded David Dejesus to the Oakland Athletics for Vin Mazzaro and Justin Marks. It seemed like almost immediately the Royals had a rotation upgrade in Mazzaro. In 2010 he posted a 4.27 ERA and had a strikeout rate of 5.0 per 9 innings. He didn’t seem like a star, but he seemed to be a decent pitcher who still had some upside.

Coming out of Spring Training the Royals made it clear that Vin Mazzaro was going to be the 5th starter and would go to Omaha to stay on track to be ready for when he was needed. Everything was going according to plan until Mazzaro went out and did this:

2.1 IP | 2 H | 5 ER | 7 BB | 3 K

That’s not a line that exactly inspires confidence in a Major League General Manager. Now granted, we don’t know the whole story. Maybe he was working on something, maybe he’s slightly hurt and maybe he was getting really pinched by an umpire and he didn’t adjust. Regardless, it’s nearly impossible to call a guy up with that kind of line at AAA and put him in a rotation spot.

The decision makes sense, but I’d still lean towards going with Mazzaro. I’m of the opinion that his bad outing was merely a blip on the radar. Yes, it was a very large blip, but nothing more. I’m also really selfish and I’ve seen what Sean O’Sullivan has done. Vin Mazzaro is shiny, new and unseen. I’d like to see him pitch and hope for a different result.

You can follow Nick Scott on Twitter @brokenbatsingle, on Facebook or reach him via email brokenbatsingle at gmail dot com. He also writes a weekly post at The Lawrence Journal-World.