On top of that, the Blues also agreed to pay a $7.5 million contract bonus O’Reilly was due by the end of the day.
Heading to Buffalo are veterans Vladimir Sobotka and Patrik Berglund, as well as Tage Thompson, who had three goals and six assists in 41 games as an NHL rookie this season. Thompson was the Blues first-round pick in the 2016 draft.
Buffalo also acquired a second-round selection in 2021.
The trade does not come as a surprise after Sabres general manager Jason Botterill declined to rule out the possibility of O’Reilly being traded earlier in the day.
Botterill would only say the asking price will go up if the Sabres were required to pay the O’Reilly’s contract bonus.
"It certainly, to me, changes the dynamic of anything from an asking price or what we’d be looking for from a trade perspective," he said.
"We’ve always said, if we are going to make any movements on our team, we certainly will look at them because of where we finished in the standings," Botterill said or a team that finished last for the third time in five years. "But it would have to make sense to make it, to improve our team."
O’Reilly completed his third season in Buffalo since being acquired in a trade with Colorado, after which the Sabres signed him to a seven-year, $52.5 million contract. He’s a dependable, two-way forward, who set the NHL record by winning 1,273 faceoffs last year.’
The Sabres also made some additions during the first day of the NHL’s free agency period.
Buffalo signed former St. Louis goalie Carter Hutton to a three-year, $8.25 million contract.
The 32-year-old Hutton has six seasons of NHL experience, including the past two with the Blues, where he split starting duties with Jake Allen. He finished with a 17-7-3 record and a 2.09 goals-against average in 32 games last year.
The Sabres had a need at goalie after electing not to re-sign third-year starter Robin Lehner and veteran backup Chad Johnson.
Hutton joins Linus Ullmark, who is pegged to make the jump to the NHL level on a full-time basis after spending the past three years developing in the minors.
Buffalo also signed goalie Scott Wedgewood, who is expected to take over the starting duties in the minors. Wedgewood had a 5-9-4 record in playing a career-high 20 games with Arizona last season.
Forward Scott Wilson returned to Buffalo by signing a two-year, $2.1 million contract. He signed a week after Buffalo elected against extending Wilson a qualifying offer to retain his rights because the team wanted to avoid the possibility of having his contract determined in arbitration.
Wilson had six goals and 14 points in 47 games with the Sabres after being acquired in a trade with Detroit.
The Sabres also signed prospect defenceman Brandon Hickey to a two-year entry-level contract. Hickey completed his senior season at Boston University, and was acquired by Buffalo in trade with Arizona last month.