In return for Leake, the Reds are receiving two minor leaguers: 21-year-old right-handed pitcher Keury Mella and 26-year-old first baseman Adam Duvall.
Leake had been seen as a likely trade candidate with the 27-year-old set to become a free agent at the end of the season and the Reds having become sellers after quickly falling out of contention.
A six-year veteran, Leake is 9–5 with a 3.56 ERA this season, with 90 strikeouts and 34 walks in 136 2/3 innings. He's been especially dominant recently, recording a 0.60 ERA over his last four starts and shutting out the Cardinals over eight innings in his most recent outing on Tuesday.
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Mella, the Giants' top prospect according to MLB.com, is 5–3 with a 3.31 ERA in 16 starts for high A San Jose this season. Duvall, who put up a slash line of .192/.234/.342 in 77 plate appearances for the Giants last season, has hit .279/.323/.548 with 26 home runs and 79 RBIs in 99 games for Triple A Sacramento in 2015.
The trade of Leake is the Reds' second significant move in the run-up to the trade deadline, following the trade of ace Johnny Cueto to the Royals last weekend.
The Giants are 56–45 this season, putting them one-half game behind the Dodgers in the National League West and two games ahead of the Cubs for the second NL Wild Card.
The non-waiver trade deadline is 4 p.m. ET on Friday.
- Ben Estes