Philadelphia (53-46) at New York (53-46)

The New York Mets obtained Johan Santana to put them back atop the NL East. Trying to make sure that doesn’t happen, the Philadelphia Phillies have brought in Joe Blanton.

With their prized offseason acquisition taking the mound, the resurgent Mets (53-46) face Blanton and the Phillies (53-46) on Tuesday night in a showdown for first place in the division.

The Mets’ 2007 collapse, which ended with them losing the NL East title to Philadelphia on the last day of the season, was the main factor in their acquisition of Santana (8-7, 3.10 ERA) in the offseason.

The addition of the former Minnesota ace didn’t change New York’s fortunes at first. Manager Willie Randolph was fired in June and the Mets were 42-44 and in third place, 5 1/2 games out of first, on July 4.

Starting the next day, however, the Mets embarked on a 10-game winning streak, and are now in position to move past the Phillies with this three-game series at Shea Stadium.

“It’s a lot better than playing them in Philadelphia,” New York closer Billy Wagner said. “I hope our fans are ready.”

The Mets, who rolled to the NL East title in 2006, are 11-2 in their last 13 games.

“We know they’re going to be geared up,” Phillies slugger Ryan Howard said. “We’ve got to be the same way.”

Howard and Philadelphia’s lineup will try to solve Santana, who’s 1-0 with a 3.00 ERA in two starts versus the Phillies this season and 1-0 with a 2.75 ERA in three career starts against them.

The left-hander, though, is coming off his worst start of the season, allowing five runs and six hits in four innings Thursday before New York came back to beat Cincinnati 10-8.

Philadelphia will counter with Blanton, who will make his first start since being picked up in a trade with Oakland on Thursday. The Phillies, who along with the Mets are also battling Florida for division supremacy, bolstered their rotation with a pitcher that won 42 games for the Athletics from 2005-07.

Blanton has not allowed a run in two starts against the Mets, going 1-0 while striking out 10 in 15 innings. The right-hander has been a disappointment this season, however, going 5-12 with a 4.96 ERA in 20 starts.

“Maybe a change of scenery will help him,” Philadelphia pitching coach Rich Dubee said. “We think he’s going to be a piece that’s going to help us get into the playoffs and further on.”

Blanton struggled again in his last start, allowing six runs and nine hits in six innings as Oakland lost 6-4 to Seattle on July 9.

The Mets defeated Cincinnati 7-5 in 10 innings Sunday to move into a tie with the Phillies, who lost 3-2 to the Marlins in 11.

Howard drove in both runs for Philadelphia, which went 1-for-6 with runners in scoring position and stranded 10.

The Phillies have lost seven of 12 since July 4. They rank 20th in the majors over that span with 50 runs, while the Mets are first with 75.

Jimmy Rollins has remained productive for Philadelphia, batting .294 (10-for-34) during an eight-game hitting streak. Rollins, though, is hitless in seven at-bats against Santana and is 6-for-25 (.240) with no extra-base hits in seven games against New York this season.

The Mets lead the season series 7-3. They’ve won three straight versus Philadelphia, totaling 23 runs and 45 hits in those games.