CHICAGO -- Bob Melvin joked that he caught a glimpse of the ninth inning of Monday’s series opener against the Cubs at Wrigley Field. The Giants manager was ejected in between the top and bottom of the eighth inning for arguing balls and strikes.

Melvin’s ejection proved to be just one moment of an eventful game on the North Side. The Giants and Cubs traded blows before Thairo Estrada delivered a knockout punch with a go-ahead, three-run homer in the ninth that pushed San Francisco to a 7-6 win.

In a game that had four lead changes, the Giants picked up their fifth win since May 22 when trailing by two or more runs in the eighth inning or later.

“We talked about it a little bit in the hitters’ meeting today, that we had a really, really tough loss a couple games ago [vs. the Angels],” Melvin said. “And every time we've had one of those, it seems like we've come back and responded well.”

Here is a look at a few crucial aspects of Monday’s win that swung momentum the Giants’ way.

Conforto and Yastrzemski’s throws

Twice, the Cubs gambled on the basepaths. Twice, a Giants outfielder made them pay.

“They’re momentum swings,” Melvin said of those big throws by Michael Conforto and Mike Yastrzemski.

After drawing a leadoff walk against Giants starter Jordan Hicks in the first inning, Mike Tauchman attempted to tag up and advance to second on a Christopher Morel drive to left field. Conforto snagged the 323-foot flyout and unleashed a strike to Estrada, nailing Tauchman by several feet.

In the fifth, Patrick Wisdom tried to score from third base on Cody Bellinger’s 245-foot flyout to Yastrzemski in right field. Yastrzemski threw a 90.2 mph strike -- his hardest throw this season -- to catcher Patrick Bailey, who tagged out Wisdom for an inning-ending double play. The Cubs unsuccessfully challenged the call and for Bailey blocking home plate.

“That was huge,” Yastrzemski said. “[Bailey] did a really good job of, No. 1, hanging on to the ball. But also manipulating himself, so that way, he wasn’t blocking the plate without having the ball.

The Giants’ win probability increased from 49.4 to 66.7 percent after Yastrzemski’s putout, which preserved what was a 1-0 lead.

Estrada’s home run

Estrada put the Giants ahead in the seventh inning, when he was hit by a pitch on the right forearm with the bases loaded. That one-run lead held for less than a half-inning, but when the second baseman stepped up to hit in the ninth, he had more room for the dramatic.

Estrada launched a go-ahead three-run homer off Cubs closer Hector Neris, pushing San Francisco’s win probability from 15.9 to 82.6 percent. And he had a feeling that moment was coming hours beforehand.

“I had not hit a bigger home run than the one I hit today,” Estrada said through interpreter Erwin Higueros. “I was very positive today. I showed up, I put the batting gloves on, I went to the cage. I got myself mentally ready. I had this feeling that something big was going to happen to me today.”

Doval’s bounceback

The Giants used eight pitchers on Sunday against the Angels. Even in a 13-6 win, they had to call upon closer Camilo Doval, who allowed four runs on four hits and two walks and got just one out.

Doval needed just 11 pitches to retire Wisdom, Morel and Bellinger in the ninth on Monday, converting his 13th save.

“It's incredible what he did,” Estrada said. “The great thing about this game is that one day you're down, but then you have the opportunity to get up the next day and do it.”

Doval’s effort was key because most of the Giants’ bullpen was down after a taxing few days. Randy Rodriguez (1 2/3 innings) and Erik Miller (1 1/3 innings) followed Hicks -- who allowed four hits and walked four batters in five scoreless innings.

The Giants got key solo homers late from Heliot Ramos, who made it 2-2 in the seventh, and Bailey, who cut San Francisco’s deficit to 6-4 in the eighth.

“We've got a grindy team,” Yastrzemski said. “We've had a couple games like this, where we've come from behind. It’s huge for our confidence, knowing that we're never out of the game. … Everyone was pretty calm and focused on what we had to do to win that game. So credit to all the guys that stayed in mentally and hung in there.”