On September 6, he attempted a cartwheel in the Wrigley Field outfield during pregame warmups and suffered a ruptured patella tendon, ending his season.

[14][15] He signed with the Oakland Athletics for the 1995 season, pitching to a 6.27 ERA in 66 innings before he was designated for assignment in July.

[17] On September 30, he pitched 6.2 innings of shutout baseball in a must-win game against Oakland to help the Angels force a one-game playoff with the Seattle Mariners.

[18] Harkey signed with the Los Angeles Dodgers for the 1996 season, but spent the entire year with the Albuquerque Isotopes in Triple-A.

[21] Harkey served as a minor league pitching coach for San Diego Padres affiliates the Rancho Cucamonga Quakes in 2000, Fort Wayne Wizards in 2001 and 2003, Lake Elsinore Storm in 2002 and 2004, and Mobile BayBears in 2005, as well as the Chicago Cubs affiliate Iowa Cubs in 2007.

[23] Under Harkey, the Yankees bullpen played a major role in their success during the 2009 season, culminating in a victory in the 2009 World Series.

[22] Harkey's son, Tony, is a former infielder for the Cal State-Fullerton Titans and Concordia University Irvine baseball team.

[27] Tony won a NAIA World Series title in 2011 with the Concordia University Irvine Eagles.

His son Cory Harkey was a tight end for the Los Angeles Rams,[28] and is now serving as a Special Teams Assistant Coach for the Buffalo Bills.