Why play Semyon Varlamov in nets against Washington? Ilya Sorokin has easily been the better of the two goalies for the New York Islanders this season. That isn't just a subjective argument, it's objectively true. Just look at the stats between the two.
Ilya Sorokin: 0.925SV%, 2.33GAA, 5.5GSAx
Semyon Varlamov: 0.912SV%, 2.85GAA, -3.3GSAx
*GSAx: Goals Saved Above expected from Moneypuck.com
So why in Sam Hill's are the Isles starting the worse goalie in what is a key matchup for their impossibly slim playoff hopes. Well, it's about playing the "hot hand" of sorts.
Why the New York Islanders are starting Varlamov in nets
I'm using "hot hand" in a different sense here. Typically, the hot hand is the goalie that's in the best current form. That goalie, again, is Ilya Sorokin. But I'm using a more contextual definition of "hot hand".
In his last three games against the Washington Capitals, Varly has been pretty outstanding for the Isles as one Isles fan indicated on Twitter. Varlamov hols a 2-1-0 record, a 0.33GAA, a 0.989 SV%, with two shutouts in his last three starts against the Caps as an Isles goalie.
Meanwhile, Ilya Sorokin, who's played Washington twice, holds a 3.5GAA and 0.875GAA with a 0-2-0 record. Clearly, Varly is much better against the Capitals. Barry Trotz told Islanders fans a while ago that they would alternate goalies based on how they've done historically against various opponents. That's what Trotz is doing tonight.
Not to mention that the Islanders have a ton of hockey to play coming up. The Isles close out the month of March with ten games in 16 days including two back-to-backs. That's a lot of hockey left to play to just keep running out one guy between the net. The Isles are going to split up that time.
What we are seeing today is their strategy on how to split up the games. Varly is historically very good against the Caps (at least as an Isles goalie) so he gets the start.