The injury Buffalo Sabres star Jack Eichel sustained in practice Wednesday will keep him out for at least the month of October.

Eichel has been diagnosed with a high-ankle sprain, and TSN Hockey Insider Bob McKenzie says the Sabres have set a loose four-to-six week timeline for recovery - though it could be longer.

Several media members witnessed the scene at practice Wednesday, and reported Eichel screamed in pain as he fell to the ice.

Eichel is entering his second NHL season, he scored 24 goals and added 32 assists as a rookie last year.

He was the second overall pick of the 2015 NHL Draft. Eichel scored one goal and added an assist in three games with Team North America at the World Cup of Hockey last month.

The Sabres open their season on Thursday night against the Montreal Canadiens. Head coahc Dan Bylsma ruled out forward Kyle Okposo for the opener with a knee injury and said the team would see how Ryan O'Reilly responded after practice before committing to his status. O'Reilly is dealing with a back injury.