That is according to former Premier League boss Alan Pardew.
The Swede is edging closer to a comeback, having worked hard on his fitness.
Ibrahimovic suffered a cruciate ligament blow in April but he is posting videos showing his knee looking strong.
Jose Mourinho revealed talks of a new deal are already underway.
And reports have suggested United could even finalise a new contract for Ibrahimovic as soon as this week.
His £75million replacement up front, Lukaku, has started life well at Old Trafford, scoring against Real Madrid, West Ham and Swansea.
“They could play together, but also it could take the weight off his shoulders”
But Pardew believes the experienced and classy Ibrahimovic is someone Lukaku can really learn from to help build his own game.
“Romelu Lukaku is the man,” Pardew wrote in his Daily Mail column.
“He looks like Manchester United’s No 1 striker, he plays like Manchester United’s No 1 striker. But he needs Zlatan Ibrahimovic to teach him a few old tricks.
“If United announce that Zlatan has signed on again later this week, it should be a relief for Lukaku.
“They could play together, but also it could take the weight off his shoulders. He will tire in what could be a long campaign and Zlatan can show him how he can lead the line.
“Give him the space and Lukaku will kill you but there were times in the game at Swansea, when it was tight, when he struggled. And that will happen against better teams.
“They won’t give him the room to destroy them. He will have to think his way through the roadblocks and he is still learning that part of his game.
“Ibrahimovic is brilliant at that, playing little one-twos, taking the ball into feet under pressure, playing give-and-go.
“Lukaku is a top signing for United and his start has proved that but he needs a little work on his finesse. Brute force can only get you so far in this league.”