The Portland Timbers' Audi 2021 MLS Cup Playoff hopes suffered a major blow during the second half of their Western Conference Semifinal against the Colorado Rapids on Thursday, with star playmaker Sebastian Blanco being forced to leave the game with an apparent hamstring injury.

As he looked to run onto a forward pass, Blanco collapsed to the ground, grabbing the back of his heavily taped left leg and immediately signaling that a substitution would be required. As he was replaced by Santiago Moreno, an emotional Blanco could be seen in tears before being comforted by Timbers head coach Giovanni Savarese.

It's a brutal blow for Portland and Blanco, who had just returned to his best following an ACL tear suffered last summer that ruled him out for the second half of the 2020 season and the start of this year.

He had seven goals and seven assists in 24 regular-season appearances (12 starts). In his last three games, including Sunday's Round One playoff win over Minnesota United, Blanco had five goals and an assist.

Following Portland's dramatic 1-0 win over Colorado, they'll now either travel to Sporting Kansas City (No. 2 seed) or host Real Salt Lake (No. 7 seed) in the Western Conference Final.