The 24-year-old broke into Aston Villa's senior side as a young teenager in 2013, and despite some controversial moments, later became captain of the first team.
Villa are still in the relegation zone and next up, they will face newly crowned champions Liverpool at Anfield.
"He's a player that they (Manchester United) need". The Norwegian manager has heaped praise on the winger on several occasions and has admitted that Grealish's addition will only further strengthen Man Utd's midfield, especially after the arrival of Bruno Fernandes during the January transfer window.
Tim Sherwood has claimed that Manchester United have already reached an agreement with Aston Villa to sign Jack Grealish this summer.
Pushed further on his claim, Sherwood said it was inevitable that Grealish would move to United, adding: "I don't think he can stay at Aston Villa, he needs to progress his career".
It is believed that Grealish's form has piqued the interest of Man United boss Ole Gunnar Solskjaer and that the club wishes to sign the 24-year-old.
According to the Express and Star, the one-time Manchester United youngster will be given the chance to impress between now and the end of the season, having caught Smith's eye with his application and attitude behind the scenes at Bodymoor Heath.
The Aston Villa number 10 has netted nine times in 30 games in the Premier League this season to help keep the Birmingham side within touching distance of Watford in 17th place.