Heung-Min Son's dramatic victor secured a stunning 4-3 victory for Spurs against League Two Wycombe on Saturday, sending the Premier League side through to the FA Cup fifth round.
Son's deflected strike from a narrow angle reduced the deficit and Janssen won and converted a penalty shortly after catching an arm across the face from Aaron Pierre.
The hosts went on to draw level but a Garry Thompson goal appeared to have sealed the win for Wycombe, only for Spurs to score twice in the dying stages to knock the visitors out of the cup.
Against the run of play, the visitors struck what seemed like a victor late on. Props to Wycombe for the performance and for pushing a big dog to the brink.
"This is the FA Cup".
They are exciting and they believed they could beat us here.
Spurs lacking strength in depth?"It is tough because you need all the squad".
Moussa Sissoko, Josh Onomah, Cameron Carter-Vickers, and Kevin Wimmer were, to put it mildly, not at their best against the Chairboys. It was hard in the first half but in the second have we increased our level.
Spurs played the final half an hour with 10-men after Kieran Trippier hobbled off in tears with a hip problem but Pochettino said he had not had a chance to assess the defender.
Gareth Ainsworth's side raced into a two-nil lead with Paul Hayes firing past Michel Vorm, first with an impressive volley and then from the penalty spot.
TOTTENHAM staggered into the draw for the fifth round of the FA Cup tonight after snatching a late, late victor in a hammer-and-tongs cup classic against League Two's Wycombe Wanderers.
"It was insane. An unbelievable game".
And, as the first half progressed and Wycombe took a 2-0 lead, it seemed a good thing that Janssen was not involved in the embarrassment.
"It is completely different to Spain and France". It is the oldest competition in the world and the teams and people try to win to lift the trophy.
Incredibly, there was yet more to come from the tie and Alli produced a wonderful solo goal to rescue a replay from Spurs with 2 minutes of regular time to play. They have done the whole town proud, me proud, and themselves proud. That's football. Today it was for us and maybe another day it is for them.
"We gave absolutely everything".
Hayes has scored in three of his last four FA Cup appearances against Premier League opposition (four goals).
Wycombe return to League Two action at Exeter City on Tuesday (19:45), before welcoming play-offs rivals Portsmouth on Saturday.