J.D. Martinez has been one of the biggest surprises of the Tigers season, but at one point, his so-called Cinderella story seemed to have struck midnight. Martinez followed up a monstrous first half by hitting just .193/.256/.325 in his first 24 games. While fans didn't exactly write him off -- a season-long OPS of .896 is still pretty darn good -- there were questions as to whether Martinez was going to go the way of Brennan Boesch, Matt Tuiasosopo, and other flash-in-the-pan Tigers corner outfielders before him.
Then, Martinez homered against the Pittsburgh Pirates and everything clicked again.
Since that home run -- his 16th of the season -- Martinez has hit a robust .321/.361/.523 with five home runs, 14 RBI, and 14 runs scored in 119 plate appearances. His home run off Jason Vargas in last night's game was his third in the month of September. He has 34 strikeouts in those 119 plate appearances, a slightly higher rate than his season-long pace of 25.6 percent.
Looking closer at Martinez's high strikeout rate, it comes as no surprise that he has been swinging and missing more often lately. His O-swing percentage, or the percentage of pitches outside the strike zone he swings at, is up from 34 percent during his off period to 40 percent in the last month. Likewise, his contact rate has gone down from 77 percent to 67.2 percent during that same time frame. His whiff rate? Up from 12.5 percent to 18 percent.
However, things get interesting when you compare these results to his first half. From his call-up until the All-Star break, Martinez hit .346/.380/.654 with a 5.9 percent walk rate and 23.4 percent strikeout rate. During his "month of shame," that .581 OPS coincided with a 7.8 percent walk rate. This latest hot streak has resulted in an .884 OPS, 5.0 percent walk rate, and 28.6 percent strikeout rate.
Yes, you read that correctly. Martinez's worst month of baseball resulted in his highest walk rate. He also had his lowest swing rate of the season during that month, at 54.1 percent. In the first half and during this last month, Martinez's swing rate has been at 56 percent or higher. While he was with the Houston Astros, J.D.'s swing rate never rose above 52.5 percent.
Has the increased aggressiveness paid off? You bet. Martinez is hitting .435/.417/1.022 on the first pitch of an at-bat this year. In a 1-0 count, Martinez's slash line improves to a whopping ..565/.565/1.478. He has hit 13 of his 20 home runs this year in the first two pitches of an at-bat. Attacking early in the count makes sense for Martinez, an excellent fastball hitter. According to Fangraphs' pitch values, Martinez ranks 15.6 runs above average against fastballs, higher than teammate Miguel Cabrera. J.D. is hitting .347 with a .639 slugging average off fastballs this season, including 16 home runs and 16 of his 25 doubles.
Overall, we are dealing with samples too small to accurately determine whether Martinez's "see ball, hit ball" philosophy is the real reason why he has broken out in 2014. His overaggressiveness has led to a strikeout rate above the league average, and the list of above average batters with a strikeout-to-walk ratio as high as Martinez's is very small. It will be interesting to see if Martinez can maintain this pace down the stretch, or if we see more selectivity out of him as opposing teams look to adjust to his free-swinging ways.