5. Aroldis Chapman
There might not have been a flashier player in recent memory than Aroldis Chapman. The left-hander took the league by storm when he arrived in 2010. No one had ever seen the type of heat Chapman was able to generate. The southpaw routinely hit 100-plus mph with his fastball and was also able to rely on his devastating slider.
Chapman was one of the best relievers in Major League Baseball during his time with the Reds. From 2010-2015, Chapman went to four All-Star Games, finished among the Top 10 for the NL Cy Young Award one year, and struck out nearly 550 batters over 319 innings of work.
Off the field issues saw the Reds trade Chapman following the 2015 season. The flamethrower wound up with the New York Yankees in 2016, and was later trade to the Chicago Cubs. Chapman found his way back the Bronx the following year and spent six seasons with the Yankees.
Last year, Chapman signed a free agent deal with the Kansas City Royals, but was traded midseason to the Texas Rangers. Though he endured some missteps during the Rangers' postseason run, Chapman was part of a World Series Championship team for the second time in his career.
After signing Brent Suter last week, the Cincinnati Reds no longer have the need for a left-handed reliever at the back of the bullpen. But it's a good bet that Chapman will find a new team before spring training begins.