Decker smacked two crucial home runs Friday and the San Antonio Missions sealed a 5-3 win over the Frisco RoughRiders in the Texas League South Division finals.
San Antonio took a 2-1 lead in the best-of-5 series, which resumes Saturday in Friday.
The Missions were locked in a 1-1 tie through three innings when Decker stepped up in the fourth and pulled a one-out solo shot off starter Carlos Pimentel, who didn't make it into the fifth.
Decker, who also doubled in a run in a Game 1 win on Wednesday, was far from done. With the game deadlocked, 3-3, after seven innings, the 24-year-old designated hitter smacked an opposite-field solo shot off reliever Richard Bleier (0-1).
Decker batted .237 with 13 longballs and 38 RBIs in 49 games during an injury-riddled regular season. The Padres' 22nd-round pick in the 2009 Draft had just one multi-homer game this year, going deep twice and driving in six runs against Northwest Arkansas on April 15.
Teammmate Jaff Decker chipped in a pair of RBI singles for the Missions, who won the division in both halves of the season.
San Antonio starter Casey Kelly, the Padres' No. 1 prospect, allowed two runs on six hits over six innings. He walked four, struck out two and threw 87 pitches.
In other Texas League action
Naturals 3, Travelers 1
Northwest Arkansas stayed alive, thanks to starter Mario Santiago (1-0), who limited Arkansas to one run on four hits over six innings. Jamie Romak, Tim Smith and Wil Myers, the Royals' No. 1 prospect, plated runs to help the Naturals avoid a sweep. Gameday box score