The pair have been good friends for a number of years prior to Lukaku's move to Old Trafford from Everton this summer.
"[Lukaku's] had a good pre-season. Scoring goals, that's what we were expecting. [Nemanja] Matic, you can see he's been working hard," Pogba told Sky Sports News.
"He's settled in the team like he was there for the whole of pre-season. We're happy. Victor [Lindelof], too, you can see his quality straight away. We have a very good group.
"We [Lukaku and Pogba] talked about it last season, wondering if one day we would play together and it's happened this season so I'm very happy. We all are. We have a good relationship."
Man United get their Premier League campaign underway on Sunday when they host West Ham United at Old Trafford.