The 24-year-old converted two crosses before finishing off a delightful team goal for his third.
And Solskjaer says the performance was a result of Martial's hard-work on the training pitch.
"The third goal was a great goal. But for me the first and the second were better. He's in the box, ready to go. We have worked on that, getting in the box in that situation more often," Solskjaer said.
"At the near post he showed composure and I think, as I said, the first goal was vital the way he turns and gets himself into a position to score from Marcus' cross. [I'm] very pleased with that.
"He's getting more and more into those position he could have had one at Spurs - a great turn and finish and a great save, he's in good form."