SAN FRANCISCO (AP) -- Ryan Ludwick narrowly beat Juan Uribe's throw home to score the go-ahead run in the sixth inning, and the NL West-leading San Diego Padres held off the San Francisco Giants 3-2 on Friday night for their fifth straight victory.
Clayton Richard (10-5) earned his third straight win over the Giants this season, helping San Diego extend its division lead to 3½ games over San Francisco in a game the Padres played under protest. It became a moot point when they won.
The Padres quieted Jonathan Sanchez (8-8), who no-hit them here July 10, 2009, after he guaranteed a sweep of San Diego following his outing at Atlanta last Sunday.
"We're going to play San Diego, and we're going to beat them three times," Sanchez said. "If we get to first place, we're not going to look back."
Sanchez's comments only added fuel to this highly anticipated weekend series between the two contenders.
In the fourth, with the score tied at 2, San Francisco second baseman Freddy Sanchez hustled to field Chris Denorfia's grounder that hit off Jonathan Sanchez, but Scott Hairston ran in front of Freddy Sanchez and caused the infielder to stop his motion. First base umpire Marvin Hudson first ruled Hairston out for interference, then the crew met about the play.
Padres manager Bud Black came out to argue. After a discussion that lasted several minutes, San Diego decided to play the game under protest.
The Padres took the lead in the fifth when a sliding Ludwick beat the close play at the plate on Chase Headley's grounder. That came moments after hefty San Francisco third baseman Pablo Sandoval ran down the line and made a forward-diving tag on Adrian Gonzalez to save a run. Sandoval's head whipped back upon impact with the ground and knocked the wind out of him. He was briefly down and examined by trainers before returning to third.
The teams, each having changed significantly, hadn't met since May 18 at Petco Park but still face off seven times after this series -- four games in San Diego in early September and a season-ending three-game series from Oct. 1-3 in San Francisco.
"This is a showdown," Black joked of the significance of this series considering it's still only mid-August. "When you get into September, that's really the line for me."
The game sure had a playoff feel with a boisterous sellout crowd of 42,722.
The Padres have won eight of the first nine with the Giants, including the initial seven matchups.
San Francisco jumped to a quick 2-0 lead against Richard, who walked leadoff man Andres Torres and allowed him to advance on a wild pitch. Aubrey Huff then hit an RBI double and later scored on Pat Burrell's groundout.
The Padres tied it in the top of the second.
Sanchez plunked Yorvit Torrealba on the left shoulder to start the inning, then Headley tripled him home and Hairston followed with a sacrifice fly.
Richard allowed six hits in six innings. He owns a 2.05 ERA in four starts against the Giants in 2010. Heath Bell pitched the ninth for his majors-leading 35th save in 38 chances. He needed nine pitches to get Burrell on a popup for the first out.
San Francisco's starters are winless over their last 10 outings, going 0-6.
The Giants acquired Jose Guillen from the Kansas City Royals earlier in the day to be their new right fielder. Guillen wasn't due to arrive in the Bay Area until late Friday and manager Bruce Bochy wasn't sure he would start Saturday.
The Giants lost for the first time in 10 tries while wearing their Friday night orange home jerseys.
NOTES: Padres RHP Chris Young threw a bullpen session of about 50 pitches. Young went on the disabled list with a strained shoulder on April 12, a move that was retroactive to April 7. He had arthroscopic surgery last August and has made only one start this season. A simulated game could happen soon and there's a chance Young could pitch for the Padres in September. "He's progressing nicely," Black said. "Like any competitor, he wants to be out there." ... San Francisco LHP relievers Jeremy Affeldt (strained oblique) and Dan Runzler (dislocated left knee) both were set to begin rehab outings with Class-A San Jose this weekend. Affeldt allowed two hits and a strikeout in one inning Friday. Runzler will start and pitch an inning Saturday. ... The Giants sold out for the 20th time, topping their 19 sellouts last season.