Tarasenko leaves the Blues with the fifth-most goals (262) in franchise history. He also ranks 11th in games played (644), seventh in assists (291) and fifth in points (553). He helped the club capture its first Stanley Cup in 2019 and was a four-time NHL All-Star with the Blues.
Mikkola heads to the Rangers with 139 games of NHL experience, recording four goals and 16 assists (20 points) with the Blues.
"I want to thank (Niko) for his time here, a fifth-round pick playing a number of games," Armstrong said "He overcame a lot of odds and was a good player for us. I wish him nothing but the best with the Rangers also."
In addition to two draft picks, Armstrong was excited to get Blais back in a Blue Note while also adding depth defenseman Hunter Skinner, who will report to the AHL's Springfield Thunderbirds.
"Geting Blaiser back, we had success with him," Armstrong said. "He has played probably his best hockey here in St. Louis, I talked to him and he's excited about coming back, (Blues Head Coach) Craig Berube knows him and how he can use him. He needs to come back in here and stay healthy and play and confirm his spot in the NHL and we have the ability to give him that opportunity.
"Skinner is someone we wanted to make sure with (Tyler) Tucker coming up, make sure we had an American League player that could go in there and support the AHL team," he added. "He's a later-round pick, just starting his career. Just based on where he was drafted, he has a big hill to climb. But he's big, he's physical, so he has some attributes we like and we'll see how that goes. I don't want to overhype or discount him, it's going to be some term and a project there. But we're looking forward to getting our development guys working with him and moving him forward."
Thanks to the deal, the Blues currently have two first-round picks at the upcoming NHL Draft, and that was something Armstrong coveted.
"You go into (a trade) trying to have players that can compliment guys sooner rather than later," he said. "A first-round pick is something I know our amateur guys are excited to have. It also gives you the ability to package that and whatever pick we may have to move up a few slots.
"First-round picks are big-time equity in the NHL, and now we have two for sure."