St. Louis Blues defenseman Carl Gunnarsson is out for the rest of the NHL season with a right knee injury. Forward Ivan Barbashev will be re-evaluated in six weeks after undergoing surgery on his left ankle. Those injuries will test the Blues’ depth with several regulars already out of the lineup. St. Louis has lost two in a row but remains in second place in the West Division. The team has been without top winger Vladimir Tarasenko for its first 20 games. General manager Doug Armstrong has said the hope is Tarasenko comes back well before the end of the regular season.