Right-hander Kevin Gausman will continue his pursuit of the lead position in the San Francisco Giants' playoff rotation when the National League West leaders wrap up a four-game home series against the San Diego Padres on Thursday afternoon.

The Giants (95-51) won the first two games of the series, including a 9-1 decision in the series opener on Monday to clinch an NL playoff spot. However, the Padres prevailed 9-6 on Wednesday to end San Francisco's nine-game winning streak.

With the second-place Los Angeles Dodgers (94-53) having won six in a row, San Francisco's division lead is down to 1 1/2 games. The runner-up in that race will be relegated to the NL wild-card game.

The Giants currently would have three solid options should they fall into that contest, with Gausman, Logan Webb and Anthony DeSclafani all pitching well of late.

After a shaky start to the second half of the season after earning an All-Star nod, Gausman (14-5, 2.65 ERA) has gone 5-0 with a 3.50 ERA in his past eight starts. His win total leads the Giants.

The 30-year-old pitched brilliantly in three earlier starts against the Padres this season, allowing just one run and lasting at least six innings in each. He went 2-0 in those starts, making him 2-0 with a 2.22 ERA in five games (four starts) against the Padres in his career.

San Diego (75-70) looms as a potential opponent for either the Giants or Dodgers in the wild-card game. The Padres, who ended a five-game losing streak Wednesday, will take the field Thursday one game behind the St. Louis Cardinals (76-69) in the chase for the last NL spot.

After getting six effective innings from Joe Musgrove in Wednesday's win, the Padres have exhausted their three healthy starters with Chris Paddack and Blake Snell both injured.

San Diego signed veteran Vince Velasquez off the scrap heap on Wednesday, and he might get a start Friday or Saturday in St. Louis.

Waived earlier this week by another playoff contender, the Philadelphia Phillies, Velasquez said Wednesday he's glad to have landed on his feet in another potential high-impact situation.

"It's unfortunate that they lost two of their starters, but I've got a lot left in the tank," he said. "I'm here to demonstrate what I'm capable of doing and help them out."

The Padres likely will resort to a bullpen game in the series finale at San Francisco. Right-hander Pierce Johnson (3-3, 2.98 ERA) is the probable opener after he allowed one run in 1 1/3 innings of relief on Tuesday. He is 1-0 with a 1.35 ERA in six career outings, all in relief, vs. the Giants.

The San Diego bullpen already has been busy in the series, having been called upon 13 times in the three games.

Four relievers were effective in the Monday loss, combining for one run allowed in four innings, but the nine who were summoned Tuesday and Wednesday served up a combined six runs (five earned) on nine hits in 7 1/3 innings.

Whoever gets the ball for the Padres would be wise to keep it in the ballpark. Eight Giants have combined for nine homers in the three games, with Brandon Belt going deep twice.

Four of the homers, all solo shots, came after the Giants fell behind 5-0 on Wednesday.

San Francisco manager Gabe Kapler said, "I was pretty proud of the way the guys fought there at the end. There was no quit in us. We were fighting all the way through the end. Our pitchers just had a tough day."

The Padres have countered with just one homer in the series, that coming off the bat of Jurickson Profar on Wednesday.