Yankees closer Mariano Rivera throws against the Texas Rangers at...

Yankees closer Mariano Rivera throws against the Texas Rangers at Rangers Ballpark in Arlington, Texas. (April 23, 2012) Credit: Getty

KANSAS CITY, Mo. -- Brian Cashman said he feels the Yankees have the pieces to overcome the loss of Mariano Rivera, who tore his ACL shagging flyballs before Thursday night's game against the Royals.

But at the same time, he acknowledged saying that is one thing.

David Robertson, who Cashman said Friday afternoon has "earned the right" to inherit the closer's role, still has to do it.

"I can't tell you he can do it until he's doing it," Cashman said by phone from his office. "It would be disrespectful for how difficult it [closing] is. We believe he has the qualifications to do it, but until they're actually doing it, you just don't know."

The 27-year-old Robertson, coming off a season in which he held the opposition scoreless in 63 of his 70 appearances and posted a 1.08 ERA, seems to have the stuff that would translate to closing. In 66 2/3 innings last season Robertson, struck out 100 and walked 35. Robertson hasn't allowed a run in 11 appearances this season. He has 18 strikeouts and has allowed three walks and seven hits in 11 innings.

"Obviously it's a big loss but we feel we have people we can turn to," Cashman said. "It's not something we can't overcome but it's somebody [Rivera] we've been able to rely on for nothing but success forever. Now it's time to turn to somebody else. We rearrange the furniture as we've been forced to do at other positions over the years and persevere."

Cashman said Rivera would remain with the team Friday night, then likely head back to New York on Saturday. The general manager also had no second-guesses about Rivera shagging balls during batting practice, a common practice for pitchers and something Rivera has done his entire career, often times looking like the most natural fielder out there.

"All pitchers are doing it from every level," Cashman said. "Pitchers shouldn't be doing home-run robbing catches, but shagging fly balls? It's been going on forever. It's nothing I plan on changing. It's just a freak accident."

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