Reynolds joined the Major League Baseball umpiring staff in 1999 after the Major League Umpires Association mass resignations. He has worked 7 Division Series (2005, 2007, 2008, 2012, 2013, 2014, and 2018), 5 League Championship Series (2010, 2015, 2016, 2017, 2020) and 2 World Series (2014, 2018). He also umpired in the 2004 Major League Baseball All-Star Game. He was the second base umpire on May 29, 2010, when Roy Halladay threw the 20th perfect game in MLB history.