DENVER -- Jason Marquis is running out of time to find his missing sinker.
He'll have two more starts to try to help the Rockies reach the playoffs.
"Oh, plenty of time," Marquis insisted. "I'll work hard in between starts, try to get the feel back. I might lighten up my throwing a little bit, we're so deep into the season. I'll watch some film, throw a nice light 'pen and try to get my feel back for the bottom of the strike zone."
The Rockies' lead in the NL wild-card race was whittled to four games on Atlanta, which beat New York 5-2, and San Francisco, which beat Arizona 5-2.
With 10 games left, the Rockies' hearts aren't racing just yet.
"If we win the rest of our series, nobody catches us," manager Jim Tracy declared.
Then, former Rockies slugger Matt Holliday will make his first visit to Coors Field as an opponent when the St. Louis Cardinals come to Colorado for a three-game series.
There's a chance the Cards will clinch a playoff spot at their hotel Thursday night, if the Chicago Cubs lose at San Francisco. That could change the competitiveness of their weekend series at Coors Field.
As the Padres proved Wednesday night, though, nothing's coming easy for the Rockies.
By not swinging at Marquis' off-target sinkers early in the count, they forced him to rely on his secondary pitches that caught more of the plate.
That patience paid off, especially for Will Venable, who hammered a flat slider for his 12th home run and added a three-run triple off a meaty pitch in the fifth, giving San Diego a 5-0 lead.
His four RBI tied a career high and helped the Padres snap Colorado's eight-game home winning streak.
"That's been the thing that I've been working on the last couple of days, just trying to tighten up the zone a little bit, just wait for the pitch I know I can hit," Venable said.
Marquis allowed six runs, five of them earned, on five hits and five walks before leaving with two outs in the fifth, failing for the third time to win his career-best 16th game.
"I just wasn't getting ahead," he said. "If I get ahead, it really doesn't matter what the other team's game plan is. I was falling behind, too many hitters' counts and I had to come back to the middle of the plate more times than I wanted to."
For the Rockies to clinch and do anything in the playoffs, it would help if they had the Marquis who was 11-6 at the All-Star break and not the version that's struggled with locating his slider over the last month while going 1-4.
Venable hit a solo home run in the second, his 12th, and added a three-run double in the fifth off Marquis, who failed for the third time to win his career-best 16th game.
Right-hander Tim Stauffer took a no-hitter into the fifth inning but left after allowing two runs on three hits, denying him the victory because he only went 4 2/3 innings.
"As a [former] starting pitcher myself, that's not ideal," Padres manager Bud Black said.
But Stauffer had thrown 101 pitches.
"I think as that inning progressed I felt as though time was running out for Tim. His pitch count was getting high and they were taking some pretty good swings and I felt the consistency from pitch to pitch just wasn't there," Black said.
Clint Barmes led off the inning with a double and scored on Seth Smith's single. Tulowitzki chased Stauffer with an RBI single that made it 6-2.
Stauffer said he knew he had thrown too many pitches, walking four in the first two innings.
"We won, I can't say a lot of bad," Stauffer said. "I would of liked to stuck in there longer, but any time you leave the game on the winning side, it's a good thing."
- The Rockies kept LF Carlos Gonzalez out of the lineup because his left hamstring grabbed on him Tuesday night.
- Venable's four RBI tied his personal high he set on July 30 at Cincinnati.