The 29-year-old center replaces defenseman Alex Pietrangelo, who was captain from 2016-20 before signing a seven-year contract with the Vegas Golden Knights on Oct. 12.
"Obviously it's very different for sure, but I'm excited for it," said O'Reilly, who will be a captain for the first time in the NHL. "It's definitely an honor to be seen in this light from the organization and the players as well. To hear from them and get their support, it's pretty amazing. I know my parents and family are very excited too. It's something that will take a little while to get used to, but it's an exciting challenge."
Forwards Vladimir Tarasenko and Brayden Schenn, and defenseman Colton Parayko were named alternate captains.
O'Reilly, who is the 23rd captain in Blues history, is entering his third season with St. Louis after being acquired in a trade from the Buffalo Sabres on July 1, 2018.
He led the Blues in scoring each of the past two regular seasons and Stanley Cup Playoffs. He won the Conn Smythe Trophy voted as MVP of the 2019 playoffs, when he scored 23 points (eight goals, 15 assists) in 26 games to help the Blues win the Stanley Cup for the first time since joining the NHL for the 1967-68 season. He was the first non-goalie in NHL history to win the Conn Smythe in his first season after being traded.
"Ryan's work ethic on and off the ice and his commitment day in and day out is second to none," coach Craig Berube said. "He leads by example with how hard he works during practices and our games and he relays the right message from our coaching staff to our entire team."
O'Reilly scored 61 points (12 goals, 49 assists) in 71 games last season after scoring 77 points (28 goals, 49 assists) in 2018-19. He scored 11 points (four goals, seven assists) in nine games in the 2020 postseason, when the Blues lost to the Vancouver Canucks in six games in the best-of-7 Western Conference First Round.
"He is a good choice," Pietrangelo said in comments published Sunday by The Athletic. "One of the hardest-working guys I know. Leads by example every day. Has succeeded in this league for a long time, and for good reason. I was happy to have him by my side for a few years. Great person, teammate and player."
Besides Pietrangelo, the Blues had other veterans depart this offseason. Forward Alexander Steen retired Dec. 17 after 15 seasons in the NHL, the last 12 with St. Louis, because of a back injury, and goalie Jake Allen was traded to the Montreal Canadiens on Sept. 2 after seven seasons with the Blues.
"There's a culture that's been built here," O'Reilly said. "It's known when we touch the ice, we're hard to play against. I think in talking with our leadership group, that's not changing. We know when we put on that Blues jersey, it's required that you will compete and make it as tough as possible on the other team. We have some different personnel and such, but overall, that is the mindset going into it. You're going to work first and you're going to trust the system. That's what we want to continue, and I think we'll be very effective."
Selected by the Colorado Avalanche in the second round (No. 33) of the 2009 NHL Draft, O'Reilly has scored 138 points (40 goals, 98 assists) in 153 games for St. Louis and 560 points (195 goals, 365 assists) in 804 NHL games for the Blues, Sabres and Avalanche.
Seven members of the Hockey Hall of Fame have been Blues captain: Al Arbour (1967-70), Bernie Federko (1988-89), Scott Stevens (1990-91), Brett Hull (1992-95), Wayne Gretzky (1996), Chris Pronger (1997-2002) and Al MacInnis (2002-04). Other notable players who were St. Louis captain include Red Berenson (1970-71, 1977-78), Bob Plager (1970-76) and Brian Sutter (1979-88).
There are two NHL teams that do not have a captain: the New York Rangers and Ottawa Senators.
NHL.com independent correspondent Louie Korac contributed to this report
