Two teams whose new-look bullpens underwent a trial by fire in the series opener will get a rematch on Saturday afternoon when San Francisco Giants vie for a second consecutive road win over the New York Mets.

Promoted Friday in the wake of the Giants having traded two pitchers at the deadline, Kai-Wei Teng will make his big-league season debut Saturday against fellow Asia native Kodai Senga (7-3, 2.00 ERA) in a matchup of right-handers.

After both teams reshaped their bullpens with trades -- San Francisco mainly subtracting, New York primarily adding -- the Giants and Mets each put four relievers to work Friday, including one pitcher each who wasn't with the team when the clubs met last week in San Francisco.

With Tyler Rogers and Camilo Doval no longer on their roster, the Giants watched Joey Lucchesi allow two game-tying runs in the eighth of the series opener after starter Robbie Ray worked seven strong innings.

San Francisco's last three relievers, however, were nearly flawless, retiring eight of the 11 batters they faced, allowing just two walks, a hit batsman and no runs.

The trio included Jose Butto, acquired Thursday from the Mets. He served up Pete Alonso's game-tying sacrifice fly -- the run was charged to Lucchesi -- before closing out the eighth.

Pitching in a spot previously reserved for Rogers, Ryan Walker got the win after a seven-pitch ninth inning protecting a 3-3 tie. Randy Rodriguez, promoted to closer after Doval's trade, survived a bases-loaded scare in the last of the 10th to close a 4-3 victory.

Ray wasn't surprised the team was able to put the trades behind them and snap a six-game losing streak in the opener of a weeklong trip.

"We still have the big pieces; the core group of guys are here," Ray said. "We didn't do a major overhaul. This team is still good enough to win. To be able to come out after a rough homestand and win the first one here is big."

With a day off Thursday and none of the four relievers having thrown more than 16 pitches in the series opener, the Giants figure to have all hands on deck again behind Teng, whose only previous major league experience came in four relief outings last season. The right-hander from Taiwan went 0-0 with a 9.82 ERA in those games and has yet to face the Mets in his career.

Teng made 25 appearances, including four starts, for Triple-A Sacramento this season, going 3-2 with a 3.67 ERA.

Senga pitched the first five innings of a 5-3 Mets' win last Sunday in San Francisco that completed a three-game sweep. He did not get a decision after allowing three runs and is 1-0 with a 6.30 ERA in two career starts versus the Giants. Senga is unbeaten in his last seven starts, going 3-0 with a 2.80 ERA. The Mets have won all seven of those games.

Ryne Stanek, Rico Garcia, Ryan Helsley and Edwin Diaz threw an inning apiece in relief of David Peterson in Friday's loss, the Mets' fourth in a row. Helsley, acquired Thursday from the St. Louis Cardinals, helped send the game into extra innings with a scoreless ninth.

Interestingly, former Giants right-hander Rogers warmed up twice in his new bullpen but wasn't summoned on either occasion. It was testimony to the new depth of the Mets' relief corps.

"Bullpens win championships," Stanek told reporters. "That's what matters."

- Field Level Media