The centre-back came in at the heart of the Eagles defence, and dealt with the pace of Anthony Martial, Marcus Rashford and Daniel James like any seasoned pro with his trophy cabinet would.
Speaking post-match, Cahill's delight at the victory and being back out on the pitch was obvious, he said: "I’m delighted to be back out there playing football first of all. To come here and win is fantastic, Manchester United are an unbelievable team, especially at home.
"We dug in all the way to the end; it's a great win."
Today's result and performance just six days after the disappointment against Sheffield United showed the character of this team, and despite not playing in that game against the Blades, Cahill wanted to make amends: "The lads were very disappointed off the back of last week, not just the result but performance too. This was a great chance to have a reaction.
"We managed the game ok; it’s difficult. You’re going to have games in the season where you are going to have a lot more of the ball but you have to expect Manchester United to have more of the ball. They’ve got three or four upfront with pace and midfielders who can pick a ball over the top so we had to be careful and manage the game well and I felt like we did that."