Vegas sent goaltender Malcolm Subban, prospect Slava Demin and a second-round draft pick to Chicago to complete the deal.
Before the trade was announced, Lehner thanked Blackhawks fans in a series of tweets and wrote that he was "really excited to join Vegas." He also wrote that he first learned he had been traded through Twitter.
Really exited to join Vegas. Going to be a ride. Can't wait to get there but please no drums at the airport I'm shy...— Robin Lehner (@RobinLehner) February 24, 2020
Lehner has been a bright spot for the Blackhawks this season, going 16-10-5 with a 3.01 goals-against average and .918 save percentage. But when combined with teammate Corey Crawford's 11-17-3 record (2.80 GAA, .915 save percentage), Chicago is in last place in the Central Division and facing a third straight season without playoff hockey.
Lehner, 28, signed a one-year, $5 million contract with the Blackhawks during the offseason, after a career-resurrecting campaign with the New York Islanders in 2018-19, when he was a Vezina Trophy finalist.
He also won the Bill Masterton Memorial Trophy for perseverance, sportsmanship and dedication; he has spoken about seeking treatment for his mental health and substance abuse after his issues came to a head during his last season in Buffalo, 2017-18.
Lehner will pair up with Vegas starter Marc-Andre Fleury as the Golden Knights gear up for a third straight postseason appearance. With 76 points, Vegas is in first place in the Pacific Division.