Sale (1-1, 1.25 ERA) allowed one run and three hits and struck out 12, and he has been strong in all three outings.
But the Red Sox (6-5) have scored just three runs for him in the starts. He has 29 strikeouts in 21 2/3 innings, allowing 11 hits.
The only run off Sale came in the third inning, on a two-out RBI single by Evan Longoria, who came to the plate 1-for-22 lifetime with eight strikeouts against Sale.
Sale got 11 outs retiring his last 10 batters, including a run of five straight strikeouts.
Leon hit the first pitch from reliever Xavier Cedeno softly to the right side and second baseman Daniel Robertson's only play was to first. That allowed Mitch Moreland -- who opened the inning with his third hit of game, a single off loser Tommy Hunter (0-1) -- to score.
Moreland greeted Erasmo Ramirez with his first homer in a Red Sox uniform in the second inning -- after Tampa Bay starter Jake Odorizzi left with left hamstring tightness. Moreland also doubled, giving him at least one in eight of the last nine games.
Matt Barnes relieved Sale and, with one out, walked two straight hitters, the second on four pitches. The count went to 2-0 to Evan Longoria, but Barnes got him to hit into a double play.
Craig Kimbrel worked a perfect ninth for his fourth save, adding Boston's 14th and 15th strikeout of the game.
Odorizzi left the game after throwing his first pitch in the second inning, trying two warmup pitches before departing. He gave up a leadoff single in the first and then retired three straight batters.
NOTES: The Red Sox honored the fourth anniversary of the Boston Marathon bombing in a pregame ceremony. ... With all players wearing No. 42 on Jackie Robinson day, Red Sox RF Mookie Betts wore a t-shirt in batting practice that read "Equality." ... Boston CF Jackie Bradley Jr., on the 10-day disabled list with a right knee strain, took batting practice Saturday and is eligible to return Wednesday. He might do a brief rehab stint before coming back sometime this week. ... RHP Alex Cobb, who hasn't faced the Red Sox since before his Tommy John surgery and is 3-3 lifetime against Boston, goes for the Rays on Sunday, facing LHP Drew Pomeranz, who pitched well and won his first time out, just off the DL.