The Rays enter the series having taken two of three games from the Boston Red Sox at Fenway Park, including Wednesday's rubber match when David Price threw eight shutout innings, gave up just three hits and blanked the Red Sox, 4-0.
B.J. Upton and Evan Longoria hit solo home runs for the Rays, who won the last two games of this three-game series after dropping the opener of a doubleheader on Tuesday.
Price (11-10) was the latest to stifle baseball's highest-scoring offense entering the game, allowing three walks and striking out six to earn just his third win since June 22.
Kyle Farnsworth pitched a perfect ninth inning to finish off the shutout as the first Rays reliever used in the series.
Davis, a 25-year-old Florida native, is 0-1 in three lifetime starts against the Mariners and most recently got a no-decision against them in a 9-6 Tampa Bay loss on June 5.
In that game, Davis lasted seven innings and allowed five hits and five runs.
He's 4-2 in nine starts since, improving his 2011 record to 8-7 a season after he went 12-10 in 29 starts in his first full-time big-league stint.
The Rays are 7-2 in his last nine outings and have scored seven or more runs five times.
On Wednesday in Seattle, Brandon Morrow (9-7) fanned 12 in six innings of one- run ball to lead Toronto to a 5-1 win over the Mariners in the decisive third game of a three-game set.
Blake Beavan (3-4) surrendered three long balls in a five-inning start for Seattle.
The Mariners attempt to bounce back with ace righty Felix Hernandez, who's won three of four starts since a three-decision losing streak that bridged June and July.
The 25-year-old reigning AL Cy Young Award winner tossed seven innings of four-run ball in a 5-4 defeat of the Red Sox on Aug. 13 in Seattle to improve to 11-10 on the season a year after he went 13-12 with a stingy 2.27 earned run average in 249 2/3 innings.
He's 3-1 in eight career starts against the Rays with a 2.29 ERA in 59 innings with 58 strikeouts.
Hernandez has allowed two runs or less in six of his last 10 starts, in which the Mariners are 5-5.
The Rays captured seven of nine over the Mariners in 2010, but Seattle owns a slight 4-3 advantage so far this year heading into the first series at Tropicana Field.