Long before kick-off, fans in No. 7 shirts were singing Ronaldo's name around Old Trafford and they were not to be left disappointed.
United took the lead in stoppage time at the end of the first-half when Mason Greenwood's deflected shot was spilled by Newcastle goalkeeper Freddie Woodman and Ronaldo reacted quickest to score from close range.
They were pegged back on 56 minutes when Javier Manquillo equalised for the visitors on the counterattack. Manchester United's players were caught out of position and Manquillo scored with a fine effort across the face of goal.
But United were soon back in front, Ronaldo getting on the scoresheet for the second time in the 62nd minute. Luke Shaw powered into the Newcastle half before poking the ball through to Ronaldo, who took a touch before shooting past Woodman.
Substitute Jesse Lingard added to the celebration with a well-taken shot from inside the box after more good work from Pogba as the Old Trafford faithful headed home to the refrain of "Viva Ronaldo."
"When you win a game you enjoy it. When you see fans being happy you really enjoy it. There were loads of expectations today. They all delivered," Solskjaer said. "Cristiano Ronaldo has developed into a fantastic goalscorer. He played a very good game, He dropped in, linked play well."
Newcastle manager Steve Bruce, the former United captain, was able to put aside his disappointment with his team's performance to appreciate Ronaldo's impact on his return.
"If there is a genuine superstar among everyone, then this kid is with what he has achieved. We have witnessed it again today. He is something else," he said.