The San Diego Padres made the most of their first crack at Major League Baseball's new extra-innings rule Thursday night, erupting for six runs in the 10th inning to emerge with a 12-7 victory over the host San Francisco Giants.

After blowing a 6-1 lead, the Padres began the top of the 10th with Trent Grisham on second base by virtue of baseball's new speed-up rule.

Grisham scored two batters later on a Tommy Pham single off Giants right-hander Tyler Rogers (1-2), and the Padres went on to add five more on a two-RBI single by pinch hitter Greg Garcia, run-scoring hits by Ty France and Fernando Tatis Jr. and a squeeze bunt by Austin Hedges.

The Giants, who were also making their extra-innings season debut, brought around their designated runner, Steven Duggar, with a pair of infield outs in the last of the 10th to complete the scoring.

Pierce Johnson (1-0), who pitched 1 1/3 scoreless inning, was credited with the win, which earned San Diego a 2-1 victory in the series.

For the second night in a row, the Giants came roaring back from a big deficit, tying the game in the eighth.

This time, they were down by five before scoring three times in the seventh on a Donovan Solano RBI double, a Wilmer Flores sacrifice fly and an Austin Slater run-scoring single.

Mike Yastrzemski's RBI triple was the key to a two-run, game-tying eighth. His hit came after Duggar had led off the inning with an infield single. Solano soon tied the game at 6-6 with a sacrifice fly that scored Yastrzemski.

Jurickson Profar and Grisham were the big hitters early for the Padres.

Profar belted his first home run of the season in the sixth inning against Giants reliever Caleb Baragar, increasing the San Diego lead to 5-1.

Grisham tripled and scored in a two-run fourth, and he doubled home Tatis to make it 6-1 in the seventh.

Neither starting pitcher got a decision.

Padres starter Dinelson Lamet left with a 5-1 lead after pitching five innings, allowing one run and four hits. He walked four and struck out seven.

The Giants' Kevin Gausman was charged with three runs on six hits in 4 1/3 innings. He struck out eight and did not walk a batter.

Profar, who totaled three RBIs, finished with two hits for the Padres, as did teammates Grisham, Tatis and France. Pham led San Diego's 14-hit attack with three hits.

Yastrzemski tripled, singled, walked twice, scored three runs and drove in one for the Giants. Solano finished with four hits, including three doubles, and two RBIs.

--Field Level Media