Alli signed for Spurs from Milton Keynes Dons during the summer transfer window and he has broken straight into their starting line-up.
It has been a big step-up for the youngster, but one that he has coped with with ease, and Mason feels his 19-year-old teammate will only get better.
“Dele’s been brilliant,” he said. “He’s a young lad, he’s come from League One last year and he’s made the step up with ease. He’s excelled and done well for the team.
“I was aware of him before he joined us, he was scoring goals almost every week when he was at MK Dons last year. He’s chipped in with a couple this year and I’m sure he’s going to get a few more.
“He’s a grounded lad, he’s doing well. He has the right people around him with the gaffer, the management staff and the players to keep him level-headed and keep him playing well.”
Alli has enjoyed a whirlwind start at Spurs, with his excellent form earning him a spot in the England senior side.
The central midfielder has astounded with his technical ability and energy, and his partnership with Eric Dier in the heart of Spurs’ midfield has been a major reason behind the Lilywhites’ good start.
Tottenham are unbeaten in 11 Premier League matches, with optimism growing at White Hart Lane about the season ahead.
Spurs are currently three points behind the Champions League qualification spots, but there is a growing hope that they could break into the top-four before the end of the term, if they keep up their current performance levels.