Vanek was absent from the Sabres' 4-3 shootout victory against the New Jersey Devils on Saturday, and the team hoped he'd able to face the Rangers at Madison Square Garden. Rolston said Vanek is close but just not ready.
"We're hoping [for Tuesday at the Carolina Hurricanes]," Rolston said. "For his best interest and the best interest of the team, we decided to hold him out [Sunday]. He won't be able to go, but we're very hopeful he'll be able to go on Tuesday."
It's impossible to overstate the importance of Vanek this season to the Sabres, who have won three straight but enter the game 12th in the Eastern Conference at 9-12-1. Vanek is tied for third in the NHL with 27 points in 20 games.
"He showed signs [of improvement], but he just can't do some of the things we need him to do," Rolston said. "He's real close though."