Backed by an offensive explosion from his teammates, Toronto Blue Jays' starter Ryu Hyun-jin defeated the Baltimore Orioles for the second straight outing.

Ryu gave up four runs on seven hits in 6 2/3 innings in a 12-4 victory at Sahlen Field in Buffalo, New York, on Saturday (local time).

Ryu improved to 7-4 for the year, while his ERA rose slightly from 3.25 to 3.41. Ryu struck out three and walked two.

In his previous start, Ryu limited the same Orioles to a run over seven innings in Baltimore.

The South Korean left-hander's final line wasn't truly indicative of how well he pitched for the most part. Ryu retired 15 batters in a row in one stretch, before a nearly flawless outing spun out of control in the seventh, when all four Baltimore runs against him were scored.

Ryu pitched around a two-out walk in the first inning. He allowed back-to-back singles to open the second inning but then wiggled out of that jam with a double play ball followed by a groundout.

Ryu was perfect from the third to the sixth, needing just 39 pitches to work his way through those four frames. His pitch count sat at only 62 after a half-dozen frames.

Meanwhile, the Blue Jays put together three different four-run innings to support their starter. Vladimir Guerrero Jr. belted his major league-leading 26th home run of the season, a two-run job, as part of the four-spot in the third inning. Then in the bottom fifth, George Springer's RBI single was followed by a three-run homer from Randal Grichuk.

In the sixth, Teoscar Hernandez delivered a two-run single with the bases loaded, before Springer and Grichuk each contributed an RBI hit to give Toronto a 12-0 advantage.

Perhaps the extended offensive half of the sixth inning threw Ryu out of his rhythm. He struck out Ryan Mountcastle to begin the seventh but then Anthony Santander lined a double to center to begin the Orioles rally.

An infield single put two aboard. After a groundout, Ryu walked Maikel Franco to load the bases. Pedro Severino made Ryu pay with a two-run single to left that broke a string of zeroes for the Orioles.

Pat Valaika had a swinging bunt down the third base line to load the bases again. Cedric Mullins then knocked a single to right to cash in two more runs that made it a 12-4 game.

That hit chased Ryu from the game and reliever Jacob Barnes cleaned up the mess by striking out Trey Mancini.

Ryu held the Orioles to two hits through six innings and then allowed five hits in the seventh alone. (Yonhap)