Jesus Montero a lock for postseason?

NEW YORK -- It looks like the New York Yankees will have one of the most-hyped hitting prospects in franchise history on their side in the postseason.

Manager Joe Girardi offered his strongest indication to date that 21-year-old rookie Jesus Montero will be on the postseason roster.

"I can't envision ... a scenario where he won't be on our postseason roster," Girardi said on Sunday morning. "But those are things that we need to continue to talk about."

Montero has more than delivered on the hyped-up billing.

He entered Sunday batting .346 with four homers and 12 RBIs in 15 games. He had four RBIs and a home run in New York's 9-1 rout of Boston on Saturday. In his last start, against Tampa on Thursday, Montero went 3 for 3 and drove in two runs.

"I've been doing a good job, just going to do my best. I'm going to help them and do whatever they want me to do," he said.

Montero entered Sunday hitting .550 (11 for 20) against left-handers. He was 7 of 32 (.219) against right-handers, but all four of his home runs came off of righties.

Because of that split, Girardi indicated that Montero would play less if the Yankees face Detroit in the American League Division Series. All of the Tigers' starters are right-handed.

Montero is likely to see more playing time if the Yankees face the Texas Rangers, who have three left-handed starters. It is unclear at this point, however, how many of those left-handers will be in the Rangers' rotation.

Girardi said of Montero's righty-lefty split: "It very well could (factor in), but every team does have left-handed relievers. And that's the bottom line."

Montero was called up in September, but he nearly made the team coming out of spring training. However, Girardi and other Yankee officials felt he pressed during the exhibition, so they sent him to the minor leagues.

Montero hit .290 with 18 home runs and 67 RBIs for Triple-A Scranton. He hit five home runs in his final seven Triple-A games. He had 40 of his RBIs in the final two months of his stay in Triple-A.

Some thought that Montero's emergence over the past month would lead the Yankees to drop veteran Jorge Posada from the roster. But Girardi said Posada will be on the roster. And he believes the 40-year-old will have a productive postseason.

"This is a guy that has a lot of experience in the postseason," Girardi said, citing Posada's success against righties this season as one reason to carry him on the roster.

It is unclear at this point if the Yankees will carry a backup catcher. Girardi believes starter Russell Martin can play every playoff game, thanks to built-in off-days in the schedule.

Regular backup Francisco Cervelli is out with a concussion and his availability for the postseason is very much in doubt.

What doesn't seem to be in doubt is Montero's postseason roster spot.

The 6-foot-3, 235-pound super-prospect grew up watching Yankee playoffs games on television in Venezuela. Now he's on the verge of playing in them.

"I'm happy, I'm happy," Montero said. "I want to stay with the team. ... I just want to help them win."

Ian Begley is a regular contributor to ESPNNewYork.com.