The midfielder – who has stated that he’s determined to add goals to his repertoire – delivered in the 82nd minute at the Stadium of Light.
He started and finished our best move of the game, initially picking out Harry Kane and continuing his run to receive Erik Lamela’s pass and clip the ball past the advancing Costel Pantilimon.
Unfortunately, he was injured in scoring and departed on a stretcher.
The first half had been even – Jermain Defoe struck the post – but we had taken control by the time of Mason’s goal. There was another scare as Jack Rodwell struck the crossbar soon after, but we could have added to our tally and finished much the stronger team.
There were near perfect conditions for football in the North East as, although the summer is fading fast, it was an afternoon of glorious sunshine, meaning we looked resplendent in our purple third kit for the first time this season.
There was a debut for Heung-Min Son and a first start for Dele Alli as injuries to Nabil Bentaleb, Mousa Dembele and Christian Eriksen meant the midfield spots were very much up for grabs.
In defence, Ben Davies took the place of Danny Rose and up front Kane reached the milestone of his 50th Premier League appearance for us after a fruitful international break with England.
Andros Townsend made the bench for the first time this season after overcoming the injury problems that he faced over the summer and would make an appearance in the latter stages of the contest.
There were some familiar faces in the opposition camp too, as our former players Defoe and Younes Kaboul lined up against us.
We were quick out of the blocks and might have had a penalty within the first minute when Kyle Walker burst into the box and his path was blocked by Patrick van Aanholt, but nothing was given.
It was a solid start from both sides with Son and Alli demonstrating several deft touches early on as we went in search of an opener. Kane looked sharp too and with 15 minutes gone fired a warning shot to the Sunderland defence when he cut in from the left and larruped a shot just over the bar.
We looked the more dangerous going forward and midway through the first half Toby Alderweireld skipped past a series of challenges before lashing a shot that was deflected into the hands of Pantilimon.
That sparked an open spell as both sides exchanged blows and the hosts came within a whisker of breaking the deadlock. Jeremain Lens found Defoe perfectly, who raced beyond our back line but with just Hugo Lloris to beat he hit the foot of the far post.
It was an entertaining game and Son impressed with his positivity, going close with a curling effort on 38 minutes. At the other end, Defoe looked a threat and brought Lloris into action on several occasions.
With one minute of the half remaining we created our best chance so far. Nacer Chadli galloped down the left and found Walker, who showed great desire to get on the end of the cross and square for Son, but his effort was blocked with the goal gaping.
Eric Dier was his usual swashbuckling self and showed great bravery and anticipation to block two late efforts to keep the score at 0-0 heading into the interval – a scoreline that was probably fair on reflection.
There were no changes at the interval and it started as a scrappier affair in the second half. Dier was our stand-out performer as he continued to read the patterns of Sunderland’s attacks and bulldoze through them.
Chances were at a premium but Lens called Lloris into action with a rasping drive on the angle near the hour mark before Mason slipped in Alli, only for Pantilimon to smother the danger with a brave dive at his feet.
A minute later Alli did brilliantly to break into the box from the left-hand side but no one was able to get a toe on the end of his excellent cross.
Townsend replaced Son soon afterwards and he was straight into the action as he beat his man and sent over a tantalising cross that was headed behind for a corner. The resulting set-play was half-cleared to Mason who sent it back in for Kane at the back post, but he misjudged his volley from a good area.
Erik Lamela was next to enter the action and with 15 minutes to go his cross was met well by Dier but Pantilimon produced another save to deny him.
The breakthrough arrived on 82 minutes. Mason fired a pass in to Kane and kept going. Kane found Lamela, he picked out Mason and the midfielder clipped the ball beyond Pantilimon for his first goal of the season. That was his last action, though, as he was injured in the process of scoring and had to be replaced by Tom Carroll.
Rodwell curled onto the crossbar two minutes later as Sunderland tried to respond, but that was Sunderland’s final chance of note. Indeed, we could have scored more as Chadli, twice, Lamela and Kane all went close in the final stages - the latter hammering straight at Pantilimon from the right side of the box. One was enough though – and we’re off and running.
Spurs (4-2-3-1): Lloris (c), Walker, Vertonghen, Alderweireld, Davies, Dier, Mason (Carroll 84), Son (Townsend 62), Alli (Lamela 66), Chadli, Kane. Substitutes (not used): Vorm, Rose, Trippier, Winks.
Sunderland (4-5-1): Pantilimon, Jones, Kaboul, O’Shea (c), van Aanholt, Defoe, Gomez (Cattermole 73), M’Vila, Toivonen (Rodwell 81), Lens, Borini (Watmore 73). Substitutes (not used): Mannone, Larsson, Graham, Coates.
Goals: Spurs – Mason 82.
Yellow cards: Sunderland – Borini 21, Jones 42. Tottenham - Vertonghen 17.
Referee: Craig Pawson.