The US international and ex-Tottenham Hotspur forward has been ruled out for the rest of the 2016 MLS season due to an irregular heartbeat.

If the Seattle Sounders are to make the 2016 MLS Cup playoffs, they will have to do so without arguably their most important player.

In an announcement many suspected was coming, Sounders general manager Garth Lagerwey confirmed to the club’s official website on Tuesday that Clint Dempsey will miss the remainder of the 2016 season as he continues to deal with an irregular heartbeat.

The 33-year-old forward’s medical issues were first made public in late-August after he sat out Seattle’s 1-1 draw at the Houston Dynamo and was subsequently ruled out of action indefinitely while undergoing evaluations.

He briefly returned to training two weeks ago following an unspecified procedure but was absent again only days later, prompting speculation that the US international could be sidelined for the rest of 2016.

Lagerwey had previously said earlier this month that the club were “cautiously optimistic” their star man would be able to return at some stage this term, but he made it clear when speaking on Tuesday that they were simply not willing to take any risks with the former Tottenham Hotspur attacker’s long-term health.

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“We simply haven’t been able to get to a point where we felt comfortable there was a realistic chance [he’d be able to come back],” Lagerwey told “We are not willing to put any pressure on this. His return to play is not important relative to his health, both short term and long term.

“One of those tests came back with some data that showed an irregularity, and we then took him out… It was something that we had found over the course of playing for us. We had been tracking and monitoring him for some time. It popped up, and it’s something we have to take care of. We can’t take any risks with something as serious as this.

“We feel that by ruling him out today, it puts us in the best position to eventually get him back hopefully for the 2017 season.”

Dempsey had recorded eight goals and two assists in 17 regular season appearances for the Sounders this season before being sidelined, scoring a brace in his last game against the Portland Timbers on 21 August to help secure his side a 3-1 win over their Cascadia rivals.

In his absence, Seattle have picked up eight points from five matches and now sit seventh in the Western Conference following Sunday’s 4-2 victory at the LA Galaxy – three points off a playoff position with five fixtures remaining and two games in hand on the sixth-placed Timbers.

Their chances of qualifying for the postseason for the eighth straight year would obviously be far greater with Dempsey on the field, but interim head coach Brian Schmetzer remains confident that his team can continue to make ground on the rest of the pack without the Texas native.

“[Dempsey is] arguably the best American field player this country has ever produced,” Schmetzer added to ahead of Wednesday night’s home game against the Chicago Fire. “You can throw [Landon] Donovan into the group, but Clint was more creative, he’s deadly in front of goal…How do you replace him? It’s tough.

“It’s a job and we have to get back to work, we have a big game tomorrow I think this team is strong enough to deal with adversity…We miss [Dempsey], but we’ve had some good results.”

In addition to sitting out the rest of the 2016 MLS season, Dempsey will also be forced to miss the US national team’s upcoming friendlies against Cuba and New Zealand next month, as well as a pair of crucial World Cup qualifiers against Mexico and Costa Rica in mid-November.

What the future holds for the 130-time capped attacker beyond this year remains to be seen, but Lagerwey gave no indication that his career could be over and confirmed that he is under contract with the Sounders through 2017.

“Clint has overcome a lot,” Lagerwey said. “And I have every hope that he’s going to overcome this as well.”

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