SAN FRANCISCO -- It's been five years since Brandon Belt got to toast a playoff berth, so the Giants first baseman was admittedly out of practice when the champagne started to flow in San Francisco's clubhouse.

"I forgot how much this burns to get in your eyes, but it burns so good,'' a beaming Belt said. "We absolutely love it.''

The surprising Giants became the first team to clinch a playoff spot this season, hitting four home runs to beat the San Diego Padres 9-1 on Monday night for their season-high eighth consecutive victory.

After finishing 29-31 during the pandemic-shortened 2020 season, the Giants have turned things around in manager Gabe Kapler's second year. They have the best record in baseball (94-50) with 18 games remaining -- guaranteeing them at least a wild card as they try to hold off the rival Dodgers for the NL West title.

"This is a pretty focused and even-keeled team,'' said Kapler, who won a World Series ring as a player with the Boston Red Sox in 2004. "You have quite a few World Series champions in that room and people who understand that this is one step in the direction that we want to go, but not the ultimate goal.''

San Francisco extended its latest hot streak by getting early power at the plate and steady pitching from the bullpen after opener Dominic Leone threw two strong innings.

Tommy La Stella homered on the fourth pitch from Padres starter Yu Darvish and Evan Longoria hit a three-run drive five batters later. Mike Yastrzemski added a solo shot in the fourth, when Belt also went deep as San Francisco secured a postseason berth for the first time since 2016.

This one was unexpected for a team that won the World Series in 2010, 2012 and 2014.

"It took us maybe half the season to get the recognition nationally, but now we understand we have a target on our back,'' Longoria said. "It doesn't get any easier from here.''

All four homers came off Darvish (8-10), struggling in his first season with the Padres after starting 6-1. The five-time All-Star lasted four innings, allowing eight runs and six hits.

San Diego fell a game behind idle Cincinnati for the second NL wild card.

"The story of the night, we got beat early on with the long ball,'' Padres manager Jayce Tingler said. "(Darvish) just didn't have the overall command. Didn't have the finish to what he usually has with the slider and cutter. Health-wise, he's good.''

After the final out, Giants players hugged on the field and coaches did the same in the dugout before heading inside the clubhouse for a bubbly celebration.

It's the earliest date the franchise has ever clinched a trip to the postseason.

"Just like most years that we won it or went to the playoffs, I don't think most people believed that we'd be in this position,'' Belt said. "It's pretty satisfying to get back here after a while of not being very good. People just kept stepping up.''

The Padres scored on back-to-back doubles by Trent Grisham and Fernando Tatis Jr. off Jarlin Garcia in the third.

Zack Littell (3-0) retired five batters to get the win. Jose Alvarez, Camilo Doval and Kervin Castro followed and combined for four scoreless innings.

Eric Hosmer and Wil Myers had two hits apiece for San Diego.

TRAINER'S ROOM

Padres: RHP Chris Paddack was placed on the 10-day injured list with right elbow inflammation, an injury he apparently aggravated playing catch before the game. That's a blow to the rotation, as Blake Snell is receiving treatment for groin tightness that limited him to 11 pitches against the Dodgers on Sunday. RHP Shaun Anderson was recalled from Triple-A El Paso to fill Paddack's roster spot.

Giants: LHP Jose Quintana was reinstated from the paternity list. OF Mauricio Dubon was optioned to Triple-A Sacramento.

UP NEXT

RHP Jake Arrieta (5-12, 7.04 ERA) makes his third start for the Padres since signing as a minor league free agent Aug. 16. Arrieta allowed three runs in five innings during his last outing against the Astros.

Giants RHP Anthony DeSclafani (11-6, 3.33) is winless in his previous four starts and has allowed six earned runs over the last 14⅔ innings.