SEATTLE (AP) — Shane Bieber pitched six scoreless innings for the second straight start, leading the Cleveland Guardians over the Seattle Mariners 5-2 on Tuesday night.

Bieber (2-0), the 2020 AL Cy Young Award winner, struck out nine, walked none and threw 55 of 83 pitches for strikes. He allowed six hits and didn't permit a runner past second base.

“Just incredible on a night like tonight,” Cleveland manager Stephen Vogt said of Bieber. “Cold, windy and just dominating out there. It’s really fun to watch two times in a row.”

In his last season before becoming eligible for free agency, the 28-year-old right-hander has yielded 10 hits in 12 innings with 20 strikeouts and one walk.

Emmanuel Clase pitched a one-hit ninth for his second save.

Bo Naylor hit a two-run homer in the fifth off Luis Castillo (0-2), who gave up four runs and 10 hits in 5 2/3 innings. Castillo has a 6.75 ERA, allowing eight runs and 16 hits in 10 2/3 innings.

“The good stuff is about to come but the only thing I can do is keep a positive mentality and not get frustrated,” Castillo said in Spanish through a translator.

Naylor is 4 for 7 in the first two games of the series.

“I just saw something hard in and tried to be ready for it,” Naylor said. “Got the hands in and got a good result.”

Will Brennan hit an RBI single in the fourth, Steven Kwan bunted for a single in the fifth as third baseman Josh Rojas threw past first for an error that allowed Brayan Rocchio to score and Tyler Freeman hit a sacrifice fly in the seventh for a 5-0 lead.

Rojas hit a run-scoring grounder in the bottom half and J.P. Crawford had an RBI grounder.

Cleveland: LHP Sam Hentges (finger) hasn’t thrown a bullpen session yet but will in the next few days according to manager Stephen Vogt. … RHP Gavin Williams (elbow) had a bullpen session on Monday and will head to the Arizona training complex.

Cleveland LHP Logan Allen (1-0, 5.40 ERA) will pitch Wednesday to close out the series against Seattle’s RHP George Kirby (1-0, 0.00 ERA).