NEW YORK -- Johan Santana will undergo surgery on his left shoulder on Tuesday at the Hospital for Special Surgery in New York. The surgery will be performed by Dr. David Altchek.

Altchek's initial diagnosis of a torn anterior capsule in Santana's left shoulder was seconded on Monday by Dr. James Andrews, who looked over Santana's MRI in Birmingham, Ala.

Although the Mets have not set a timetable on Santana's return, Dr. Jonathan Glashow, co-chief of sports medicine at Mount Sinai Medical Center, has indicated that Santana will likely not be able to throw a baseball at full strength until at least mid-March.

That would place Santana's return to a big league mound back until June or July of next season.

Manuel excited about youth movement

NEW YORK -- Even with the Mets out of contention in September, manager Jerry Manuel still sees something to be excited about at Citi Field.

"When you have youth involved, there's always some excitement and anticipation as to what they're able to do," Manuel said, singling out Ike Davis, Josh Thole and Jonathon Niese's performances. "They can become integral pieces to build a championship team."

It's important to note that the players Manuel mentioned specifically have been with the team beyond September. That's because the manager cautions against basing too much on performance this late in the season.

"You try to not evaluate in spring and September," Manuel said. "But if that's the only thing you have to measure with, then you have to put something into it."

Two of the Mets' starters in this four-game set with the Pirates, Dillon Gee and Jennry Mejia, are each starting in the big leagues for the first time this month.

Grand slams continue to elude Mets

NEW YORK -- A rather bizarre entry may already have been made on the Mets' to-do list for Spring Training 2011 -- "Work on grand slams, hitting them and not surrendering so many."

There is good reason for a few skill sessions about salamis come February. These strangely functioning Mets of 2010 have produced an imbalance of unlikely proportions in the statistical resume of their first 140 games. Entering their game against the Pirates on Monday night, they have hit no slams and surrendered 11.

Remarkable, but there's more. They have hit the fewest -- two other teams have one each -- and have allowed the most in the big leagues. Yes, these Mets seem to go to extremes to make the point about their strangeness. Not hitting a slam in 143 games is not so uncommon. The Mets of 2007 hit none in 162 games, that after hitting a big league high (10) the previous season.

But they have hit merely eight since '06 and none in the 202 games since Angel Pagan slammed the D-backs at Citi Field on Aug. 1 last year. And they have allowed 15 since Pagan's, the 15th coming on Labor Day in Washington. One other team in history has allowed as many as 15 without hitting one of its own.

The Mets' 202 games without is nothing close to a record. Indeed, the Angels were the team that hit none while allowing 15, thereby creating the arcane distinction that the Mets now share. And the Angels' slam-less streak spanned the equivalent of four seasons, lasting from 1971-75. But the Mets' 0-15 ratio has a chance to evolve into a singular modern standard for "hold the salami."

The Mets were batting .208 in 120 at-bats with the bases loaded through Sunday. Only the Mariners had a lower average in those circumstances, .207 in 111 at-bats, but they had three slams.

But let us not overlook a slam of a different sort that these Mets have achieved. Their two victories in three games in D.C last week allowed them to win a road series for the fourth time this season. Each of the four series victories have come against a team in last place -- the Nationals, Sept. 6-8; the Pirates, Aug. 20-22; the Indians (a sweep), June 15-17; and the Orioles (a sweep), June 11-13.

There's your not-so grand slam.

The Mets didn't exploit every last-place team. They did play the D-backs on the road while the Snakes were in last place, as they still are. But the 'Backs slammed, so to speak, the Mets with a three-game sweep on the Mets from July 19-21. The Mets didn't play an American League West entry this season, however.

Manuel sticking with Duda in left field

NEW YORK -- Manager Jerry Manuel is sticking with the struggling Lucas Duda in left field, confident the rookie will break out of his 1-for-29 slump.

Duda was called up on Sept. 1 and picked up his first Major League hit two days later -- a double against the Cubs. Since then, however, he's 0-for-18.

"There's tremendous life in his bat," Manuel said. "I see bat speed. I see a guy with the ability to hit the ball in both directions with pop.

"We haven't seen it manifest itself in games."

Duda, who ascended quickly through the Mets' farm system this season, has said that nerves from his first callup to the big leagues have influenced him at the plate, and that might be part of the reason Manuel is running him out in left each day.

"He has to play," Manuel said. "The only way [to overcome nerves] is to go out between those lines day in and day out, and make it a place of comfort rather than a place of anxiety and frustration. Once he has a couple two-hit games, I think he'll take off."

Tejada will look to get going against lefties

NEW YORK -- Ruben Tejada will be back in the Mets' starting lineup on Tuesday and Wednesday, according to manager Jerry Manuel. Manuel is hoping the young second baseman can do some damage against a pair of Pirates southpaws in Zach Duke and Paul Maholm.

"What I'd like to do -- against those next two lefties -- is try to keep him going in a direction of getting over .200. That's probably important to him to have some success there," Manuel said. "I still think he'll be, not a great hitter at this level, but decent enough to be a complementary piece if all the other pieces do what they're supposed to do."

Tejada has batted just .188 in 61 games with the Mets this season, and that's after a relatively promising start at the plate. In mid-June, Tejada had a 10-game hitting streak, and his average has been up as high as .270 for the year. Since the start of July, however, he's 14-for-103, good for a .136 average.

Tejada has had more success in a small sample against left-handers, with a .250 average in 44 at-bats.

Luis Hernandez earned the starting nod again at second on Monday. Hernandez, himself a Minor League callup, is hitting .250 in 15 games with New York.