Newcastle had held on until the 83rd minutes in the game at Wembley this afternoon with the score at 0-0.
But then a shot from Son was straight at Dubravka but the goalkeeper somehow let the ball go through him and it was a Spurs goal and another costly error from the 30-year-old Slovakian goalkeeper.
And this was our 8th successive defeat at Wembley since we tore apart Manchester City 3-1 in the 1955 FA Cup final.
Newcastle put in another spirited performance but it was the terrible late error by the Newcastle goalkeeper that cost us a point this afternoon in the early kickoff game.
The game was watched by owner Mike Ashley.
Son scores after 83 minutes
Newcastle had 3200 faithful fans making the journey to London today and we could have had another excellent result.
Benitez fielded an unchanged side and new loan signing Antonio Barreca was a substitute.
As we expected, Spurs had all the possession early but they found things difficult against a very well organized Newcastle side.
Lucas Moura had a good effort from a header after 18 minutes and then Lamela hit the woodwork.
Matt Ritchie broke down the left and it ended up with both Rondon and Perez getting in shots that were blocked.
Just before the break former Newcastle forward Moussa Sissoko had a shot blocked by goalkeeper Dubravka and the danger was cleared.
Rondon came close just 5 minutes into the second half when a DeAndre Yedlin cross was headed against the post by the impressive Newcastle number 9.
Tottenham were pushing for the go-ahead goal but then Fabian Schar made a magnificent clearance off the line to keep Newcastle in the game.
But Newcastle were defending like their lives depended on it – but then it was all for nothing as Dubravka failed to shot a stop from Son that was straight at him.
And that’s the second terrible error by Dubravka this year after he spilled a shot in the Manchester United 2-0 defeat at St. James’ Park.
The fans got their first look at Antonio Barreca who came on near the end.
This will all be about Dubravka’s error, but let’s not forget this was some terrific defending by Newcastle as our players played their hearts out once again.
We cannot forget that today.
Newcastle: Dubravka; Yedlin, Schar, Lascelles, Lejeune, Ritchie, (Barreca, 86); Perez, Longstaff, Hayden, Atsu (Kenedy, 82); Rondon.
Subs not used: Woodman, Manquillo, Manquillo, Fernandez, Clark, Joselu.
Tottenham: Lloris, Trippier, Alderweireld, Sanchez, Vertonghen, Winks, Sissoko, Eriksen, Lamela (Rose, 78), Lucas (Llorente, 60), Son (Dier, 89).
Subs not used: Gazzaniga, Foyth, Walker-Peters, Wanyama.
Goal: Son 83
Referee: Andre Marriner (West Midlands)