Superstar Western Bulldogs forward Sam Darcy has been subbed out of his side’s AFL clash with St Kilda after a concerning knee injury. Darcy landed awkwardly after attempting to take a contested mark in the forward 50 late in the first quarter of Sunday night’s contest and immediately fell to the ground in pain. WATCH THE VIDEO ABOVE: Sam Darcy goes down with concerning knee injury. Know the news with the 7NEWS app: Download today Replays showed the 21-year-old talisman’s left knee hyperextending the wrong way in a cringe-worthy motion. Darcy got up and limped off alongside Bulldogs medical staff, going straight into the rooms for assessment, but was soon subbed out of the game. “Darcy does not look good,” Brian Taylor said as the big man awkwardly got to his feet. Nick Riewoldt added: “I had one really similar, a similar-type hyperextension where I’d never done an ACL, and that’s where my mind went straight away, and it ended up just being a rupture of the capsule, which was a one or two-weeker. “So, hoping that that mechanism is not as bad as it looke for Sam Darcy. “There’s a bit of a hush around the ground, isn’t there?” Sam Darcy went down with a cringe-worthy knee injury. Credit: Channel 7 Erin Phillips provided an update at quarter-time. “A real hush went around Marvel Stadium when Sam Darcy did go down with that knee injury,” she said. “He went straight into the rooms. “Hopefully we’ll have more of an update at half-time, but you never like seeing great players go down, and hopefully that’s no more than just a hyperextension.” Darcy pictured limping in the rooms after sustaining the injury. Credit: Channel 7 He was replaced by second-game substitute Cooper Hynes. Darcy, the son of club great Luke, kicked 38 goals last year in a breakout campaign and added 14 as the Bulldogs’ most prolific forward through their first five games this season. Widely regarded as a generational talent, Darcy signed a four-year contract extension with the Bulldogs last December, which ties him to the club until the end of 2029. More to come ...