Last year with the T-Bones, Rainwater started 21 of his 22 appearances, posting a 4.78 earned run average in 137.1 innings pitched. He pitched three complete games and one complete game shutout. The right-hander possessed control on the mound with a 4.28 strikeout-to-walk ratio, allowing only 18 free passes compared to 77 strikeouts.
In 2011, the Deridder, LA native pitched for the Grand Prairie Airhogs, his first season of independent baseball. He led the American Association with 14 wins, in just 20 starts. He threw two complete games, struck out 91 batters and allowed only 27 walks in 134.2 innings pitched. The 27-year-old was drafted in the round 4 of the MLB Amateur Draft out of Deridder (LA) High School in 2003. Rainwater spent eight seasons in the Tigers system, making it as high as AAA. During those eight seasons, Rainwater saw time as a starter and out of the bullpen. He pitched in 203 games, posting a 34-40 record, with a 4.11 earned run average in 628.1 innings pitched. He struck out 492 batters compared to the 241 batters he walked over those eight seasons.