 At the 2010 FINA Short Course World Championships in Dubai, Plummer won a gold medal in the 4×100-meter medley relay for his contributions in the heats.Plummer also competed in the 50- and 100-meter backstroke in Dubai but finished out of medal contention in both events.At the 2011 World Aquatics Championships in Shanghai, Plummer placed fifth in the final of the 100-meter backstroke with a time of 53.04.