Rockies sign former Giants closer

DENVER – One day after acquiring relief pitcher Seunghwan Oh from the Toronto Blue Jays, the Rockies have added yet another quality arm to bolster their bullpen depth.

Colorado has signed former Giants closer Santiago Casilla to a minor league deal after his subsequent release from the Oakland Athletics last week.

As a reliever with the A’s this season, Casilla pitched to a 3.16 ERA with a 1.21 WHIP over 31.1 innings, which has been valued at 0.5 WAR.

Casilla spent some time on the 10-day DL in late May with shoulder discomfort. Since his return from rehab on June 12, he’s thrown 9.2 innings with a 2.79 ERA, with seven hits, six walks and nine strikeouts.

The Dominican born reliever joins a relief corps in Albuquerque that includes Jerry Vasto, Carlos Estevez and Brooks Pounders.

During his time with the San Francisco Giants between 2010-16, Casilla won three World Series and amassed 123 saves.

This move shows both the GM Jeff Bridich is still in buying mode and that he isn’t locked into one concept of what type of player he wants to acquire moving forward. Adding Oh is a move that will immediately impact the 25-man roster and could even, given certain circumstances, end up being an addition of a player who closes out vital games down the stretch.

On the other side, Casilla is depth for now, but excellent depth at that. His experience and Bud Black’s familiarity with the long-time NL-West reliever, are likely to serve him well at earning a 40-man spot for September should he perform well in Albuquerque.

The roster crunch will be a difficult one for Colorado, though. Of the players currently on the 40-man, 37 have MLB experience and can be seen as either potentially quite valuable moving forward but maybe just not yet like Jerry, Sam Howard, or guys who have been valuable in short spurts and have even been relied upon and come through in critical moments like Pat Valaika, Noel Cuevas, Mike Tauchman.

Then there’s the third category of guys who are still a little farther away but who have proven themselves to be important to the organization. This includes starting pitcher Jesus Tinoco, outfielder Yonathan Daza, and catcher Chris Rabago.

A case could be made for keeping each of these players and a case could be made for most that even if they were to be designated for assignment to clear room for Oh or someone in the near future (Peter Lambert, Brendan Rodgers) they could pass through waivers and return to the Rockies system.

Though, they lost lefty-reliever Zac Rosscup to the Los Angeles Dodgers in such a fashion.

If Colorado becomes especially concerned that they might lose one of these valuable players in a roster crunch, they may decide it more prudent, should a proper proposal be on the table, to have any further trades include at least one player already on the 40-man roster.