WHAT IT MEANS: Ruben Tejada snapped the fourth-longest homerless drought among active major leaguers, and Jon Niese rebounded from a flop in Arizona by taking a scoreless effort into the sixth inning, as the Mets beat the Giants 2-1 on Wednesday at AT&T Park -- despite squandering bases-loaded opportunities in each of the final three innings.

With Frank Francisco expected back Friday in San Diego to reclaim the closer’s role, Bobby Parnell converted the save, retiring Buster Posey, Hunter Pence and Marco Scutaro in order.

Tejada opened the game with a homer against Giants ace Matt Cain, snapping a drought of 628 at-bats without a home run. Tejada trailed only Jamey Carroll (1,261 at-bats), Chris Getz (869) and Ben Revere (763), in terms of homerless streaks, according to the Elias Sports Bureau.

Tejada’s only other major league homer came on Sept. 5, 2010, against the Cubs’ Marcos Mateo. The drought was the 14^th-longest in Mets history.

Cain required 30 pitches to navigate the first inning, but he limited the damage to Tejada’s solo homer by retiring Jason Bay on a flyout to right field to strand two runners. Cain was pulled for a pinch-hitter with the Giants trailing 2-0 in the bottom of the fifth, and his pitch count at 97. It matched Cain’s shortest outing of the season. He also went five innings while earning a win at the Angels on June 18.

Niese did walk a pair of batters in the first inning. But in the ex-Phillie Pence’s first at-bat with his new club, Niese stranded the runners by coaxing a foul pop fly. Until Posey’s two-out homer in the sixth pulled San Francisco within 2-1, the lone hit against Niese was Scutaro’s leadoff single in the second inning.

The southpaw was coming off an outing in Arizona in which he allowed eight runs (six earned).

The Mets loaded the bases in the seventh, eighth and ninth, but failed to score each time. The first two opportunities came courtesy of four walks, a hit batter and a Giants error.

With one out in the seventh, sidearm lefty Javier Lopez entered and coaxed a 6-4-3 double play from Ike Davis as the Mets failed to build on their one-run lead.

An inning later, the Mets loaded the bases with none out against Clay Hensley.

Josh Thole then grounded into a force play at the plate. Posey tried to complete the double play at first base. The ball struck Thole in the left shoulder and ricocheted into right field, seemingly allowing a run to score. However, the umpiring crew ruled Thole was inside the first-base line when he was struck and called him out. A walk to Justin Turner -- who was pinch-hitting for Niese -- reloaded the bases, but Tejada grounded out against Brad Penny and the Mets still had a 2-1 lead. Tejada finished 3-for-4 with a walk.

Bay hit into a lineout double play to end the top of the ninth.

WHAT’S NEXT: The Mets complete the second leg of their three-city trip when Chris Young (2-5, 4.58 ERA) opposes left-hander Barry Zito (8-7, 3.89) in Thursday’s 3:45 p.m. ET series finale.