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Mauricio Pochettino's Tottenham are not far away from being a top-level team.

His first 11 has proven itself competitive with England's best teams—it boasts wins over Chelsea and Arsenal, as well as an entertaining defeat at Anfield.

The problem for Pochettino is that his squad lacks the necessary depth to push for success on multiple fronts.

Spurs' biggest week this season ended in a pair of painful defeats. First they were knocked out of Europe by an unremarkable Fiorentina side, and then they didn't do themselves justice in the Capital One Cup final.

Beaten 2-0 by Chelsea, Spurs were unable to take control of the match in the way they did when they thrashed the Blues at White Hart Lane, and they were picked off.

Tottenham are currently forced to rely on inferior reserves like Vlad Chiriches, Roberto Soldado and Paulinho.

Worse than that are the crop of players who lack even the quality to be named in the squad while they continue to draw wages. Emmanuel Adebayor, Etienne Capoue and Younes Kaboul are all experienced international players who signed for significant transfer fees and are paid handsomely.

Pochettino is unlikely to be able to rid himself of all six players in one summer, but it is realistic to believe that chief scout Paul Mitchell can find a new player in each of defence, midfield and attack ahead of next season.

Spurs are unable to attract players who are far beyond the quality of their current lineup. The fees, wages and European demands make such transfers unviable.

Instead, Spurs need to pursue players who can be effective substitutes and fight for a place in their lineup.

Many of Spurs' current players loaned out across the Football League will be given the chance to find a place in Tottenham's squad over the summer. Players like Alex Pritchard, Milos Veljkovic, Tom Carroll and Ryan Fredericks each have a realistic chance of breaking in under Pochettino.

New signings like Dele Alli and DeAndre Yedlin will also be given their chances to impress.

Looking outside of the current payroll, Tottenham have many options, but they must narrow their search to players who fit the necessary parameters.

With that in mind, Villarreal's Luciano Vietto, versatile Torino defender Matteo Darmian and Derby County midfielder Will Hughes would be perfect signings.

The 21-year-old Vietto has scored 18 goals and laid on eight assists in his first season in Europe. Far from an unknown, Vietto was La Liga's player of the month in December. He also has four years remaining on his contract, and though he would not be cheap, Villarreal have shown a willingness to deal in the past.

Vietto is small, quick and turns well. His close control is impressive, and he is tougher than he looks, riding challenges like a more experienced striker. The Argentinian can play in a variety of positions and is both a confident finisher and a creative force.

Crucially, Vietto could both play with and in place of Harry Kane, who cannot be expected to be Spurs' only source of goals next season. Vietto would lighten the load.

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Darmian is a an experienced, rugged Italian defender. A voracious tackler, Darmian is a throwback to classic Calcio defenders.

Usually a right-back, Darmian is also capable of playing on the left or centrally. A full international, Darmian has been capped nine times and was right-back of the year last season when he helped Torino to secure a rare European place.

He could likely be signed for far less than comparable players like Toby Alderweireld, who would also be an excellent, although expensive, option.

Darmian's versatility would allow Pochettino to consider alternative defensive formations, while his athleticism would make him an effective partner to the more languid Jan Vertonghen. He would be the first player to threaten Kyle Walker's monopoly on the right-back position, and that competition would surely be good for the England man.

Will Hughes is the biggest name on this list for many reasons. Young, English and reportedly a Liverpool transfer target, Hughes is an outrageously talented player.

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Still only 19 years old, Hughes has already made well over 100 appearances for the Rams. Manager Steve McClaren has been an excellent steward of young players throughout his career, and he has carefully managed Hughes while in charge at Derby.

Hughes has three years remaining on his contract at Derby and is a very highly rated young player. He will come at a premium, but his signature would give Spurs a potential reserve midfield of Carroll, Alli and Hughes. The three young, gifted English players would provide balanced options and genuine strength in depth behind Nabil Bentaleb, Ryan Mason and Christian Eriksen.

If Tottenham were to sign Vietto, Hughes and Darmian, they would substantially upgrade their squad and possess the depth necessary to better compete with the big teams next season.