Graves, 22, has four goals and seven assists (11 points) in 57 games as an alternate captain with the Hartford Wolf Pack this season. The Yarmouth, Nova Scotia native has 21-41–62 totals in 207 career AHL games.
The 6’5″, 226-pound defenseman has yet to appear in an NHL game and was originally drafted by the Rangers in the 4th round (110th overall) of the 2013 NHL Entry Draft.
He will report to the San Antonio Rampage.
Bigras, 23, has one assist in 15 games with the Avalanche this season. He has one career NHL goal and three assists in 46 NHL games. In 20 games with the Rampage (AHL), Bigras has 1-5–6 totals this season.
The 6’1″, 190-pound, Orillia, Ontario native made his NHL debut on January 14, 2016 and was originally drafted by Colorado in the 2nd round (32nd overall) of the 2013 NHL Entry Draft.