The Sabres have asked Americans defenseman Rasmus Ristolainen, who played 19 NHL games earlier this season, if he wants to represent Finland at world juniors, according to the Rochester Democrat and Chronicle.Ristolainen said yes, although he’s not sure if he’ll be allowed.The 19-year-old, the No. 8 pick in June, is out with a possible concussion this week after being sucker-punched Friday.