Seattle announced on Friday that forward Clint Dempsey will miss Sunday's game against Portland while he undergoes medical evaluations for an irregular heartbeat.
Portland and Seattle already have a fierce rivalry, but their clash this weekend has added spice as both teams are fighting for their playoff lives.
Clint Dempsey is being tested for an irregular heartbeat and will miss the Seattle Sounders' game on Sunday against the rival Portland Timbers.
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Steven Gerrard has hinted that he could be keen to take on a coaching role with England if he calls time on his playing career in November.