After 16 seasons, 13 with the New York Yankees, Andy Pettitte has announced his retirement, ending any speculation he’ll pitch in 2011.

Yes, he may still make a come back during the season, and certainly most Yankee fans hope he will, but for now, let’s operate on the assumption that he’s gone for good.

The Yankees finally know Pettitte’s status and they can stop wondering, but that’s about the only affect his announcement should have on the team’s operations.

From the time the season ended, general manager Brian Cashman has had to build his team as if Pettitte would not be a part of it this season. Everyone is asking who the Yankees will add to replace Pettitte, but why are they asking that now?

If the Yankees believed Pettitte had been learning towards retirement this entire time, they should have already found a replacement for him, and if he happened to come back, that would have just been icing on the cake, but it wasn’t necessary for their offseason plans.

There were statements from general manager Brian Cashman more than two weeks ago that Pettitte would not be returning in 2011.

On January 12, Cashman told reporters that Pettitte “is choosing at this stage to not start 2011.” He then clarified his statement, saying he meant to say “pitch” instead of “start,” meaning Pettitte wouldn’t pitch in 2011.

“Andy’s been very communicative [with me] on this issue. Right now, he’s not playing. If he decides to play, it will be for us,” Cashman stated. “He’s a Yankee, from start to finish. I don’t think he’s determined whether he’s officially finished, but is choosing at this stage to not start 2011.”

That was almost three weeks ago. So why is the question of how they’ll replace Pettitte in the starting rotation being asked now? Surely Cashman has been under the impression that he wouldn’t have his prized lefty (no, not Cliff Lee) in the starting rotation this season.

It seems Pettitte made it perfectly clear that he wouldn’t pitch in 2011. He is set to officially announce his retirement today, but Cashman and the Yankees had all the indications they needed three weeks ago.

They should have prepared for this already.

After missing out on Cliff Lee, the Yankees’ starting rotation is questionable at best. After CC Sabathia, they have to worry about the sophomore slump of Phil Hughes and the up-and-down antics of A.J. Burnett. Ivan Nova is expected to fill the No. 4 spot, but the fifth spot is still very much up for grabs.

Cashman has brought in Bartolo Colon and Freddy Garcia to compete for the last spot in the starting rotation, as well as in-house candidate Sergio Mitre. All those additions came before Pettitte’s official announcement, so why do they suddenly need to replace him now?

“He’s not delaying anything, he’s not pushing us back, he’s not hurting us,” Cashman said at a fundraiser on January 26. “He was honest up front from the very beginning. Of course we’d like him to play.”

The questions about how the Yankees would replace Andy Pettitte should have started two months ago, not this week. Cashman knew that, which is why he’s spent the majority of this offseason trying to add starting pitching.

While many Yankees fans love to get on Cashman for not bringing in Lee or Carl Crawford, or not wanting to sign Rafael Soriano, you have to give him a little bit of credit: he built his offseason around the assumption that Pettitte wouldn’t be in the starting rotation come Opening Day.

There were certainly good starting pitching options available earlier in the offseason, such as Brandon Webb, Jeff Francis and Chris Young, but the Yankees have added their fair share of starters to fill out the rotation because Cashman had abandoned his hope a month ago.

If one day this season Andy Pettitte’s face shows up on the big screen at Yankee stadium and Susan Waldman has another nervous breakdown on the radio, Yankees fans everywhere will rejoice.

For now, though, they must come to terms with the fact that the reliable left-hander wont be taking the mound in 2011. Brian Cashman certainly did… a month ago.

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