SAN FRANCISCO -- The Mets spent the offseason making several key upgrades to their roster, both in the lineup and starting rotation. But no one has had a bigger impact on the team's hot start than a man who's been here all along.

Pete Alonso continued his recent torrid stretch Monday night, going 3-for-5 with a three-run homer, his 11th of the season, as New York blasted the Giants 13-3 at Oracle Park.

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Alonso has recorded multiple hits in five of his last six games, raising his slash line to .288/.356/.524. His 40 RBIs rank second in the Majors to José Ramírez and lead the National League, while his 11 long balls are tied for first in the NL.

“What he's doing is special,” Jeff McNeil said. “It's fun to watch him take at-bats every single night, putting together great ABs, hitting the ball hard and just driving in a ton of runs for this team. He's been pretty amazing.”

Alonso led an 18-hit barrage Monday, including three home runs as the Mets improved to a season-high 14 games above .500 at 29-15.

“To do it consistently is hard, when everybody knows what you're capable of and you're still doing it,” manager Buck Showalter praised. “Pete loves to play. He likes competing. He's a consistent personality every day.”

Over the last six games, Alonso has gone 12-for-26 with three homers and 11 RBIs. It took him just 44 games to reach 40 RBIs for the year, tied with Bernard Gilkey’s 1996 season for the fastest in franchise history.

“It doesn't surprise us at all what Pete's doing,” J.D. Davis said. “It's cool, vintage Pete and he's getting locked in, as well, so it's going to be fun to watch him get things going.”

Added McNeil: “I've seen it my whole career, watching him come up. So nothing new to me and [he'll] continue to do it for a long time.”

Of course, it’s not just Alonso producing the offense. McNeil and Mark Canha also homered for the Mets, whose 13 runs marked a season high. Francisco Lindor added a two-run double to give him 500 career RBIs.

“There’s a lot of potential in this offense,” McNeil said. “We put together really good at-bats and we’ve got a lot of guys who are putting the ball in play and taking real good at-bats in big situations.”

New York is tied for second in the Majors with 207 runs scored this year, an average of nearly five per game.

“The guys continue grinding at-bats,” Showalter explained. “Good things happen when you keep the want-to going like these guys have. They just got into a pass-the-baton thing.”

David Peterson, recalled from Triple-A Syracuse before the game, was the beneficiary of that run support, though he might not have needed it. The left-hander allowed two runs in six innings with six strikeouts to earn his second win of the season.

“It’s always more fun to pitch with a lead,” Peterson said. “When the offense scores runs, it’s my job to go out there and put up a zero and get them back in the dugout and keep them in a rhythm for hitting. They did a great job tonight just stacking runs up and giving us a good cushion.”

Monday also marked another special occasion: Showalter’s 66th birthday. Asked if a Mets win was sufficient as a gift, the skipper smiled and responded with one word.

“Yes.”