After growing up in Pinner[2] England and going to Aldenham School, Wallace attended Jacksonville State University, in Northeast Alabama, as a freshman in the 2010–11 season before turning professional.

He was the OVC Freshman of the Year and held the record for lowest round in school history with a 10-under 62 in the F&M Bank APSU Intercollegiate.

Wallace won his second European Tour event in March 2018, Hero Indian Open, beating Andrew Johnston in a playoff, making a birdie at the first extra hole.

[6] He followed that up with a victory at Made in Denmark in September 2018, collecting birdies at five of the last six holes before coming out on top in a four-man playoff.

He qualified for the DP World Tour Championship and shot a round of 60 on the Saturday, including nine consecutive birdies on the back nine,[12] ending the week in joint second place.