Sandow picked up a hamstring tear and Evans injured his shoulder, with both replaced in the first half.
The loss of the pair didn’t stop Warrington’s charge, with the Wire inflicting Wigan’s second Super League defeat of 2016.
Warrington coach Tony Smith said they will know more when Sandow is scanned.
“I’m looking forward to when Chrissy returns because, like everyone, I think he’s fantastic to watch,” he said.
“Unfortunately he has a bit of a hamstring issue but some of the stuff he was doing was magical. We thought Rhys had dislocated his shoulder but it looks more like ligaments.
“We need to put them in cotton wool for the next week.”
Smith was pleased with his side getting the result in a tough game.
“It was tough, we couldn’t rotate in the second half,” he said.
“We used four goalkickers due to various knocks! We’re showing, at times, exactly what we’re capable of.”
“What pleases me is the character our guys are showing in all sorts of situations. Some of the efforts of our forwards were unbelievable. We carried the ball strong, our boys ran hard through the line and were very physical.”
Despite the loss, Wigan coach Shaun Wane was pleased with his players’ performance.
“I think the best team won, Warrington were very good,” Wane told Sky.
‘I’m very, very proud of my players. I thought there was some great efforts and I thought we could have got them. I thought we had a chance to win it.
“To lose in that manner with 600 grand on field is a good effort.”