The 23-year old had two bones in his right leg fractured and will now start the long road to recovery with the likelihood that he will not play again this season.
Sounders officials and players were devastated when the talented winger went down and now have to find an apt replacement within their squad to keep the promising start to their season going.
"It's a big blow for our team ... now it's, 'How do we adjust?' " said coach Sigi Schmid. "Other people have to step up."
General manager Adrian Hanauer added: "We'll start thinking about how it affects the team (on Saturday) and how we move on.
"We have a deep team - we've said it a lot - and we're going to have to prove it."
Whilst teammate Brad Evans made it clear that the playing group would have to bind together to make up for Zakuani's absence.
"We've talked about depth all season," said Evans. "It's something that the coaches brought in: a number of guys who can play at any minute and make an impact.
"Now it's up to guys stepping in and contributing the best they can."