SAN DIEGO -- Chris Denorfia hit a pinch-hit two-run homer with no outs in the ninth as the San Diego Padres rallied for a 2-1 victory over the Cincinnati Reds before 24,050 fans Monday night at Petco Park.
Denorfia drilled the first pitch over the center-field wall off Reds' closer Aroldis Chapman, who walked Yonder Alonso to lead off the ninth.
The loss wiped out a strong outing by Cincinnati starter Mike Leake, who blanked the Padres on four hits in seven innings. Leake recorded five strikeouts and issued two walks. He retired 12 of the last 13 batters he faced, the lone one being Everth Cabrera, who reached on an error in the fifth.
Reliever Luke Gregerson (6-5) retired the Reds in order in the ninth for the victory.
San Diego starter, Sean O'Sullivan, allowed a run on five hits with five walks and one strikeout in six innings.
The matchup between O'Sullivan and Leake featured two products of San Diego-area high schools. Leake played at Fallbrook, while O'Sullivan prepped at Valhalla High in El Cajon.
The Reds (59-48), who lost their fourth in a row, have managed just three runs in their last four games. San Diego (49-58) won its third straight.
The Reds broke up a scoreless contest in the fifth when Derrick Robinson, who led off the inning with a triple to right-center, scored on Cesar Izturis' grounder to first base.
It was the Reds' first run in 22 innings. They hadn't scored since the seventh inning of Saturday night's loss to the Dodgers.
Cincinnati loaded the bases after Jay Bruce doubled and Xavier Paul walked with two outs in the fifth, but O'Sullivan got out of the jam when Paul was forced at second.
The Reds also loaded the bases in the first, but failed to score as O'Sullivan got Paul to foul out to third baseman Chase Headley to end the inning.
NOTES: Reds 2B Brandon Phillips was out of the starting lineup. Manager Dusty Baker said he wanted to give the All-Star a rest. ... Cincinnati CF Shin-Soo Choo missed the game with a twisted left ankle. Choo was hurt sliding into second base during Sunday's game against the Dodgers. His status is day-to-day. ... Padres LF Carlos Quentin didn't start Monday's game against the Reds because of a "slight tweak of the knee," manager Bud Black said. Quentin, who had 20 RBIs in July, tied for third best in the National League entering play Monday, hurt his left knee Sunday during an at-bat at Arizona. ... Reds RHP Jonathan Broxton is scheduled to begin a rehab assignment at Triple-A Louisville on Tuesday. Broxton has been on the disabled list since June 15 with a strained right elbow.