If you look at the number of games started by the Spurs players you can see who Mauricio Pochettino relies on, a set of 12 players with the rest, notable Harry Winks, chipping in with substitute appearances.
Premier League Statistics
Harry Kane Centre Forward 23 20 14
Victor Wanyama Defensive Midfielder 25 25 2
Christian Eriksen Midfielder 25 24 5
Kyle Walker Right-back 26 24 0
Dele Alli Attacking Midfielder 20 22 11
Eric Dier Defender/Defensive Midfielder 23 21 0
Jan Vertonghen Central Defender 29 20 0
Danny Rose Left-back 26 18 2
Toby Alderweireld Central Defender 27 17 0
Mousa Dembélé Central Midfielder 29 16 0
Son Heung-Min Attacking Midfielder 24 14 7
Hugo Lloris Goalkeeper 30 22 0
Vincent Janssen Centre Forward 22 5 1
Moussa Sissoko Midfielder 27 6 0
Erik Lamela Attacking Midfielder 24 6 1
Ben Davies Left-back 23 5 0
Harry Winks Central Midfielder 21 2 1
Kevin Wimmer Central Defender 24 4 0
Michel Vorm Goalkeeper 33 3 0
Kieran Trippier Right-back 26 1 0
Marcus Edwards Midfielder 18 0 0
Josh Onomah Midfielder 19 0 0
Georges-Kévin N'Koudou Midfielder 22 0 0
Cameron Carter-Vickers Central Defender 19 0 0
Kyle Walker-Peters Defender 19 0 0
Pau López Sabata Goalkeeper 22 0 0
We therefore have, from a squad of 26 players, 14 who have started 6 or less games, which rather suggests that Pochettino doesn't think they are good enough, given the number of injuries we have had to contend with this season.
Two of those are goalkeepers so we can excuse them and Winks is getting developing from the subs bench, but that still leaves 11 players, Janssen, Sissoko, Lamela, Davies, Wimmer, Trippier, Edwards, Onomah, N'Koudou, Carter-Vickers and Walker-Peters.
Janssen has shown hard work but little else, Sissoko isn't a winger, Lamela has allowed outside issues to affect his focus, Davies is competent, Wimmer clearly hasn't developed as we would have wished, Trippier has performed decently enough, Edwatds has had an injury but isn't near first-team standard yet anyway, Onomah has stagnated or even gone backwards, N'Koudou isn't first-team standard yet, carter-Vickers is being trained for the future and Walker-Peters is simply a development player.
That back up set simply aren't good enough yet and many of them won't be around for the long-term so will need upgrading in the summer. It could be far busier than some are expecting.
Further THBN Reading
Sissoko only cost Spurs £17m, now wanted by AC Milan
Wrong tactics- Spurs set out not to lose and fail
The Gary Neville solution to Spurs problems is simple to fix
It's time Tottenham embraced Sports Psychologists
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