CHICAGO -- The Giants’ weekend trip to Wrigley Field was supposed to be about Kris Bryant returning to the North Side of Chicago, but another ex-Cub made sure the story of Saturday afternoon’s game centered around him.

Tommy La Stella, who played for Chicago from 2015-2018, was right in the middle of the action in San Francisco’s five-run second inning, driving in two runners with a two-out single to right field. Then, as the Giants were in the middle of breaking the game open in the top of the fifth, La Stella launched a towering shot that hit off the right-field video board.

La Stella became the fifth player of the season to hit the right-field board at Wrigley Field, and the three-run shot -- only the third homer of his career at Wrigley Field -- punctuated the Giants’ 15-4 victory over the Cubs.

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The win improves San Francisco’s record to a Major League-best 92-50, and the Giants now lead the Dodgers by three games in the National League West. San Francisco is a perfect 5-0 on the road trip, with only Sunday’s series finale remaining. With the club’s magic number to clinch a playoff berth down to four, the Giants could do it as early as Monday.

“I think everybody in our clubhouse expects to be in the postseason,” said Kevin Gausman, who earned his 14th win and struck out his 200th batter of the season in the victory. “We believe that we're the best team in baseball right now, and so I think [we're] playing good baseball and we're a dangerous team. More than anything, I think we're just focused on ourselves and doing what we have to do tomorrow to win tomorrow's game.”

San Francisco’s win came as the result of another dominant group effort from the lineup. La Stella led the team with five RBIs, while Brandon Belt and Evan Longoria contributed three apiece and Mike Yastrzemski knocked in two of his own. Each of the starting eight position players had a base hit -- LaMonte Wade Jr. completed the feat with an RBI single in the ninth -- and all but Buster Posey crossed the plate at least once.

But even though seemingly everyone on the Giants had a piece of the pie, it was La Stella’s rocket and drop of the bat that provided the highlight.

La Stella is generally patient at the plate. He’s comfortable working deep into counts, and he has the ability to foul off close pitches to make opposing pitchers work even harder. As evidenced by the fact that he saw at least three pitches in five of his six at-bats and at least seven pitches in three at-bats, La Stella has no problem waiting for his pitch.

With two men on base in the fifth inning against Cubs reliever Manuel Rodríguez, apparently he didn’t need to wait very long. On the very first pitch of the at-bat, La Stella turned on an inside fastball and launched it a Statcast-projected 409 feet at 106.8 mph off the bat.

“He's a pest up there,” Gausman said. “He makes you work, he always has quality ABs, he sees a lot of pitches, and that's what he does well. That's his bread and butter. He's gonna make you work and make you make a mistake. 

“And then he'll also come out there, swing at the first pitch and hit a three-run home run.”

La Stella has struggled after coming off the 60-day injured list on Aug. 4 (.227 batting average from then through Sept. 10), but Giants manager Gabe Kapler hadn’t lost faith that his leadoff hitter could rebound in short order.

“We trust that the best version of Tommy is going to be an excellent leadoff hitter,” Kapler said prior to Saturday’s game.

And with his 3-for-6, five-RBI game, La Stella clearly rewarded his manager’s vote of confidence.

“Everybody always says [it is] the process, not the result, but like it or not, it is a game of results. When they're not there, it's frustrating,” La Stella said. “But I think the staff here were so consistent in the work that we put in, just trusting that it's going to show up. They've been nothing but reassuring and reaffirming of all the work that we're doing.”

“We know that all players -- not just Tommy, but all players -- go through rough patches, and it's really important that we hang in there with them through those patches,” Kapler said. “Remember who they are, help remind them who they are, and trust that that'll come out over a longer period of time.”