DBacks trade for RHP Carlos Rosa from Royals

According to the DBacks Twitter account, they have traded SS Rey Navarro for RHP Carlos Rosa from the Kansas City Royals. Rosa will report to Reno.

Rosa is a 25 year old from the Dominican Republic. He was signed as an international free agent in 2001, and has made appearances in the majors in 2007 and 2008, appearing in 9 games with an ERA of 3.21. Originally a starting pitcher prospect, he's been working out of the bullpen since the start of the 2009 season with a 4.43 ERA and a 4-9 record.

Royal Revival listed Rosa as their #14 prospect in the system in February.

[Edit by Jim] More analysis after the jump

While I imagine that this trade has been brewing for some time, yesterday's outing by the bullpen - the latest in another line of dismal showings - probably made it a necessity, if only to stop a mob with pitchforks from storming Chase Field. Though the AP report disparaged it as "a swap of minor leaguers," that seems far more the case for Navarro than Rosa, even if our new pitcher will initially report to Reno - I've a feeling his stay there probably won't be long. We'll look at him in more depth further down the story.

But what of the player we're losing? Navarro is from Puerto Rico and signed for the Diamondbacks as a 17-year old - he turned 20 in December, and had been appearing for Visalia in High-A. As noted in the comments, his rep is supposedly good defensively, though made 29 errors in 118 games last year, so even if errors are not a great measure, there seems to be room for improvement. He is certainly a light-hitter with almost no power as yet, just four home-runs in 272 minor-league games, though does have a good number of doubles. 

One point worth noting is, that this is already Navarro's fourth year in the minors, and so he needs to make the majors by the end of 2012 or he'll become a minor-league free-agent. Given he's only in A-ball, that would seem unlikely. My basic rule of thumb is, it's hard to dislike a trade when you've never actually heard of the player you're giving up. While Navarro may turn out to be useful down the line, that is far from certain.

Rosa is much closer to be being major-league ready, as you'd expect, given his age. He was initially a starter, but the Royals converted him to a reliever at the end of 2008 - seems a little surprising, as his numbers in the rotation that season were not bad (eleven starts and a 4.09 ERA). In 49 appearances and 83.1 innings since going to the pen, he has an ERA of 4.43, but gives Rosa a Fielding Independent MLE (Major-League Equivalence) of 4.24, which is fairly healthy.

It's a little surprising that the Royals would opt to trade him, since they are in almost as much need of bullpen help as we are here in Arizona. They had the worst relief ERA of any team in the American League in April, at 5.77 - almost a full run worse than the next-highest figure. I'd have said that Rosa would have deserved a shot in the major-league pen: while admittedly, shortstop is universally regarded as the weakest position in their farm system, the more pressing need appears to be for immediate relief help, and Rosa was decent in two (admittedly brief) stints in the majors, with a 3.21 ERA in 14 innings.

Royals prospects analyst Greg Schaum discusses the trade, and quotes an unnamed source as saying about Rosa, "He is not resilient enough to be taken seriously as a RP. I wonder if the Diamondbacks will consider moving him back to the rotation." There also seems to be some concern over a recent drop in Rosa's velocity. Schaum adds,:"Former Royals assistant GM Muzzy Jackson is now with the Diamondbacks and he was the guy that drove the Callaspo for Billy Buckner trade a couple of seasons ago. I would imagine he played an integral part in this trade."

Right, enough on this trade. I've got a Gameday Thread to write up!