The Made In Chelsea star, 32, completed a 260-mile journey from London to Manchester earlier this month, despite suffering a calf injury on the first day.
The pair have been training together as part of the England team, reportedly held a 'peace dinner' before the match to 'ease awkwardness' over Louis, 33, dating Sam's ex Zara McDermott , 28.
Sam, 32, has insisted there are 'no hard feelings' after his ex-girlfriend Zara McDermott, 28, moved on pretty quickly with the singer, 33, following their split in December.
The men are both on the same England team for Unicef, but tried to not to draw attention to themselves, although at one point, Louis was caught staring at Sam.
Louis Tomlinson and Sam Thompson are seen in first awkward exchange as they finally come face to face for the first time at Soccer Aid training on Thursday.
The former Love Island star, 28, announced the two-part series, Zara McDermott: Stalked, last year and previously said it had been 18-months in the making.