Depleted bullpen caves in seventh during Nats' 5-3 loss

SAN FRANCISCO - The Nationals will be getting much-needed bullpen reinforcement Sunday when new closer Mark Melancon joins the club following his trade from the Pirates. But before that happened, they still needed to get through the latter innings of this afternoon's game against the Giants. And that proved a significant challenge.

Three relievers combined to give up a pair of runs in the bottom of the seventh, helping hand San Francisco a 5-3 victory at AT&T Park.

Forced to turn to his 'pen early after rookie Reynaldo Lopez piled up 92 pitches in only four innings, Nationals manager Dusty Baker tried to get as much as he could out of long man Yusmeiro Petit. The rubber-armed right-hander churned out 2 2/3 innings, but loaded the bases in the seventh and let the go-ahead run score on a sacrifice fly before finally getting pulled.

Lefty Oliver Perez, pitching for the fourth time in five days, walked the only batter he faced to reload the bases. Blake Treinen then walked in an insurance run, throwing only one strike to pinch-hitter Trevor Brown.

Baker was working with a depleted and exhausted relief corps. Sammy Solis had pitched three straight days. Shawn Kelley had closed the previous two nights. Jonathan Papelbon, who has now lost the closer's job to Melancon, was unlikely to be used unless absolutely necessary. And Felipe Rivero was no longer available, already en route to join the Pirates as one of the pieces of today's trade.

Lopez, making the second start of his big league career, didn't have to deal with his greatest affliction from his first start (too many pitches over the plate with his fastball). Instead, the young right-hander was done in by his inability to find the plate at all too many times.

Lopez issued five walks in his four innings of work, two of those batters eventually coming around to score during a three-run bottom of the fourth that also included a bases-loaded double by Eduardo Nunez.

By the time that inning ended, Lopez's pitch count stood at 92, so Baker decided not to press the issue any more and hand the game to Petit.

The Nationals also knocked out San Francisco's starter, Jake Peavy, after four innings, driving up the right-hander's pitch count with some long at-bats and well-timed hits.

Anthony Rendon's two-out, two-run homer in the top of the third (which came moments after Bryce Harper drew a walk on a borderline 3-2 pitch) gave the Nats the game's first lead. Danny Espinosa's RBI double an inning later scored Ryan Zimmerman all the way from first base and extended the lead to 3-0.

The Nationals, though, did little else at the plate the rest of the afternoon, unable to return the favor to the San Francisco bullpen.