Adam Duvall hit a two-run, walk-off home run in the bottom of the ninth inning to lift the Boston Red Sox to a 9-8 victory over the visiting Baltimore Orioles on Saturday.

Duvall's two-run shot just over the top of the Green Monster was his second homer of the game and capped a 4-for-5 effort. He finished with five RBIs, three runs and was a single shy of the cycle.

The Red Sox, who trailed 7-1 after 2 1/2 innings, received a second life in the final frame after Baltimore left fielder Ryan McKenna dropped Masataka Yoshida's fly ball that, if caught, would have ended the game. Yoshida scored on Duvall's game-winning homer.

Rafael Devers (3-for-5) and Justin Turner (2-for-4) had multiple hits, while Alex Verdugo and Enrique Hernandez also went deep for the Red Sox.

Kenley Jansen (1-0) was victorious, striking out two during a scoreless top of the ninth. Boston's previous three relievers -- Josh Winckowski, John Schreiber and Chris Martin -- combined for four scoreless innings.

Austin Hays became the second Oriole to go 5-for-5 in as many games, matching the effort of Adley Rutschman in Thursday's Opening Day effort. Hays hit a homer and two doubles.

Ryan Mountcastle and Cedric Mullins also homered.

The Orioles are the first team in MLB history to steal five bases in each of the first two games of a season.

Felix Bautista (0-1) took the loss.

The Orioles started fast for the second straight game, as Mountcastle and Hays ripped first-inning home runs against Boston starter Chris Sale, who allowed seven runs on seven hits with two walks and six strikeouts in three innings.

Duvall tripled into the center-field triangle and scored on a wild pitch, cutting Boston's deficit to 3-1 in the second.

After tacking on another run in the third, Mullins ripped a three-run homer to deep center later in the inning to extend the lead to 7-1. Verdugo and Duvall tagged Baltimore starter Dean Kremer for two-run homers, pulling Boston within 7-5 in the home half of the frame.

After Zack Kelly relieved Sale, Anthony Santander drove home Mountcastle with a double for an additional Orioles run in the fourth.

The score remained 8-5 until Hernandez's leadoff homer over the Monster in the seventh.

Duvall later had a ground-rule double to make it 8-7, setting up the wild finish.