5 MLB Pitchers Who Have Taken a Huge Step Forward in 2017

Felipe Rivero, RP, Pittsburgh Pirates

Prior to the 2016 non-waiver trade deadline, the Washington Nationals really needed a closer, so they went out and acquired Mark Melancon from the Pittsburgh Pirates in exchange for Taylor Hearn and Felipe Rivero. Fast-forward to 2017, and the Nats had one of baseball's worst bullpens before making more trades.

You know what would've been helpful in the early part of the season? Having Rivero, who's put together a career year in the Pittsburgh bullpen.

In throwing 77 innings last season between Washington and Pittsburgh, he did post a career-high 28.1% strikeout rate. However, his 10.1% walk rate was also high, as was his 4.09 ERA (despite a 3.30 SIERA). But this season, it looks like pitching coach Ray Searage worked a little more magic with the hard-throwing reliever.

Through 62.2 innings pitched, the southpaw has an eye-popping 30.6% strikeout rate to go along with a 6.6% walk rate and 2.73 SIERA. After allowing line drives more than 21.0% of the time in each of his first two big league seasons, that number has dropped to 17.6%. His hard-hit rate allowed has also dipped down to 24.8% in 2017, which is part of the reason why his BABIP allowed has dropped more than 100 points compared to last year (.312 to .207).

Already able to run up his fastball to an average velocity of just under 96 mph, it's gone up a couple more ticks this year, as he's averaged 98.4 mph on that offering. After opposing hitters posted a 149 wRC+ off his four-seamer in 2016, that number has slid down to 37 this season.