'I thought there was one guy we were going to pursue that could make our team better, and it was him,' MacLellan said.
Matt Niskanen is not expected to miss much time after getting hurt Wednesday, but it raised the question of a possible need for insurance during the playoffs.
The Capitals sit atop the league standings, so they'll be hesitant to tinker too much ahead of the trade deadline.
"I think you have to use everything, every resource," Trotz said. "I think the stats are good. They're not a bad thing. Stats are good for illumination."
Johansson contract was awarded in arbitration last summer.
After two summers of major moves, the Capitals' lone significant addition was depth forward Brett Connolly.
Expect free agency to be quiet for the Capitals now.
The last time the Capitals had the 26th overall pick, they drafted Evgeny Kuznetsov.
Alex Ovechkin wins the Rocket Richard Trophy for a sixth time after again scoring the most goals in the league.
'We're waiting for the salary cap number to come out, and then we make our decisions based on what we perceive to have on the cap, what room and what space we have left,' the Capitals' GM said.