In 2010, right-handed reliever Joel Peralta had to settle for a minor league contract with the Washington Nationals, and rightfully so. Peralta came into the 2010 season with a career ERA of 4.61 and he was allowing 1.4 homeruns per nine innings pitched. He was no more than a mopup reliever.
The Nationals were rewarded with a terrific season by Peralta as he posted a 2.02 ERA and struck out 49 batters in 49 innings while allowing only five unintentional walks. But the Nationals decided to non-tender Peralta a contract after his success and the Tampa Bay Rays signed him two weeks later to a one-year $925K deal.
To thank the Rays, Peralta would go on to post a 2.93 ERA and strike out 61 batters in 67.2 innings and walking only 15 unintentionally. Peralta's success allowed Joe Maddon to work him in some high-leverage situations and Peralta post a +1.39 WPA.
Peralta's success in back-to-back seasons was enough proof for the Rays to sign him to a one-year $2.175M deal. Peralta's newfound success relied heavily upon his success with the fastball. Prior to 2010 his wFB was a pathetic -28.5 and a pitcher who cannot work successfully off of his fastball is not a pitcher for long in the Major Leagues.
From 2010-2011 Peralta's wFB is +24 and his wFB/C (value of his fastball per 100 pitches) is +2.47, good for the second best mark in all of baseball with a minimum of 110 innings pitched. Mariano Rivera is the only player who has had more fastball success and no other pitcher over that time has a wFB/C over 2.0.
His success with the fastball is largely thanks to his location of the pitch and the fact that he is throwing his splitter more often than ever before with a career high 24.8% of the time last year after posting a career high of 23.8% in 2010.
He makes his living working the fastball away from both right-handed hitters and left-handed hitters. Take a look:
Peralta has also increased his fastball usage over the past two seasons. Prior to 2010 he used the pitch just under 50% of the time and increased it's usage to 53.1% in 2010 and 55.4% in 2011. He also ditched his slider as his splitter usage increased. Using the fastball more frequently allows for his splitter to be more effective.
Peralta also uses his fastball early and often, allowing it to set up the splitter as his go-to out pitch. He uses it 62.2% of the time as his first pitch, 57% of the time in 1-0 counts, and nearly 75% of the time in 2-0 counts and decreases its usage once he gets that first strike.
Peralta's fastball velocity has remained consistent throughout his career but his usage of the pitch and the sequencing have not. I believe his success with the pitch is in large part thanks to his newfound approach of using it more often and using it early in the count to setup his splitter.