Ben Davies scored his first Tottenham goal while Heung-Min Son was also on target as Spurs beat Aston Villa 2-0 in the third round of the FA Cup at White Hart Lane. Here are five talking points.

1. Is Spurs’ Plan B becoming their Plan A?

Mauricio Pochettino has generally favoured a 4-2-3-1 formation during his time at Tottenham but he has been experimenting with different systems this season and has become much less predictable.

Spurs have looked increasingly comfortable, confident and dangerous when using a three-man defence and wing-backs, and Pochettino used that set-up for the third game in a row today, following the impressive victories over Watford and Chelsea.

It seems that, rather than being an alternative, the 3-4-2-1 formation (or a variation of it) is becoming Pochettino’s go-to system – and justifiably so.

It did not work quite so well today though. With Villa sitting deep and Spurs struggling to break them down, the Lilywhites seemed overloaded in defence and light in the final third.

It took 70 minutes but Pochettino eventually made a key tactical change, bringing on Georges-Kevin Nkoudou in place of centre-back Toby Alderweireld – and it immediately paid off as Spurs got the crucial breakthrough.

2. Vincent Janssen struggles again

The summer signing badly needed a confidence-boosting performance against Spurs’ Championship visitors – and ideally a goal - but this was another deflating outing for the striker.

The 22-year-old, who was left out of the matchday squad when Spurs faced Chelsea on Wednesday, looked rusty from the start and lost possession on a number of occasions.

He played his part in a couple of attacking moves around the edge of the box but that is grasping at straws and Pochettino withdrew the Dutchman in the 59th minute – another blow to his fragile self-esteem.

Spurs went on to score twice in his absence, with Son – who replaced Janssen up front – netting the second goal.

3. Other squad men make positive impressions

While Janssen flopped badly at the Lane, Pochettino will be pleased with the contributions of some of his other little-used reserves.

Carter-Vickers had a solid outing in defence – albeit against a side who offered little as an attacking force – while the lively Nkoudou came off the bench and immediately delivered the cross which gave Ben Davies the chance to head in his first goal for the club.

The first half was a dire affair which lacked quality and this side would probably struggle against better opponents, but the majority of Spurs’ squad men will be better off for this outing.

4. Does Josh Onomah need a loan move?

It is never good news for reserve players when they are omitted from second-string line-ups, and 19-year-old Onomah had to make do with another cameo appearance in the final minutes when the game was effectively over.

Pochettino apparently likes to keep his best youngsters close to him, rather than loaning them out – but Onomah’s lack of game time cannot be helping his development.

Meanwhile, Tom Carrol’s Spurs career is surely over. The 24-year-old started both of the League Cup ties earlier in the season but has not appeared since then and he was omitted from today’s matchday squad altogether.

5. Can Spurs challenge for the trophy?

Tottenham are overdue a good FA Cup run to underline their improvement and their status as one of the Premier League’s top teams - they have failed to reach the last four since 2012.

The Lilywhites reached the Capital One Cup final in 2015 but have struggled to make an impact in the cup competitions since then.

These are early days in this season’s FA Cup but Spurs have secured their place in the fourth round. How far can this squad go?

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