Pirates Keep Collecting

The Pirates have traded for Diamondback infielder John McDonald in exchange for a PTBNL, per Ken Rosenthal of FOX Sports and  Jon Heyman of CBS Sports.

McDonald, 38, appeared in 70 games as a shortstop, second baseman and third baseman last year, posting a .249/.295/.386 batting line with six home runs and an OPS+ of 79. The 14-year vet is a solid glove guy, but in his many years in the league, his lifetime WAR in 2.9.

He's in the second season of a two-year, $3M contract and will earn $1.5M in 2013 before his walk year.

Who knows what it means to Josh Harrison, Jordy Mercer and Ivan DeJesus, who have all had good springs? We're guessing that since they've got their glove guy for the bench, Harrison is the front runner to claim the other spot on the pine, with Mercer and DeJesus headed to Indianapolis.

Mercer beat McDonald in the field last season, with a 9.6 UZR/150 versus McDonald's 8.5. Mac's bat was better, but we're talking an OPS+ of 79 for McDonald and 76 for Mercer; so not much gap there. And Mercer is a decade younger and would make a million bucks less. But Mercer does have an option...

And that could be the logic behind an otherwise seemingly illogical deal. With Clint Barmes in his walk year, the FO may have decided to bring in a glove-first guy for the bench so that Mercer can start at Indy. There, he would get regular PT with a chance to compete for the big team's starting job in 2014.

Then again, maybe Clint Hurdle just wanted a veteran on the bench; he's decidedly squeamish about putting youngsters on the field if he can help it. So who knows?

But whatever the reason, John McDonald is a Bucco now. We'll find out the cost soon enough, when the PTBNL is sent to Arizona and when the Bucs trim someone off their 40-man roster (they'll probably DL Chase d'Arnaud) to clear space.