Leicester's Vardy limps off with hamstring injury
Vardy appeared to hurt his left hamstring while chasing a pass in the first half at the King Power Stadium.
He was treated for several minutes before trying to resume playing, a move which lasted just seconds before he again fell to the turf clutching his leg.
This time the 33-year-old was forced to come off as Kelechi Iheanacho replaced him in a game where Leicester were leading 2-0 at half-time.
Vardy's injury will be a major blow for Leicester if he is out for a significant period of time.
He is the Premier League's top scorer with 17 goals this term.
Brendan Rodgers' side are third in the Premier League as they bid to qualify for next season's Champions League via a top four finish.
While Vardy has retired from international duty, his fine form had prompted suggestions England manager Gareth Southgate might try to tempt him back into the fold ahead of Euro 2020.
Southgate has been hit by injuries to strikers Harry Kane and Marcus Rashford in recent weeks.