Tottenham Hotspur have joined the race to sign Everton left-back Leighton Baines who could also be the subject of another offer from Manchester United in January.

David Moyes was keen to be reunited with the England defender at Old Trafford but two separate offers were rejected by Everton who were determined to keep hold of one of their most valuable assets.

The Daily Mail reports that Manchester United are still keen to sign Baines when the transfer window opens next year and are planning to offer £15m plus out-of-favour winger Antonio Valencia.

United's defence has come under fire this season and Patrice Evra particularly struggled in the 4-1 loss to Manchester City, also failing to cover himself in glory more recently as Sunderland took a shock lead against the champions at the Stadium of Light.

Moyes is said to want Baines as a replacement for Evra as he does not feel that understudy Alex Buttner is ready to be the first choice left-back.

However, it seems Manchester United may have some competition as the Mirror report that Tottenham boss Andre Villas-Boas is also interested in trying to persuade Everton to part with the defender.

Spurs have loaned out Benoit Assou-Ekotto to QPR leaving Danny Rose as the only natural left-back in the squad, with Kyle Naughton and Jan Vertonghen providing cover when the former Leeds youngster is in need of a rest.

Villas-Boas has an incredibly strong squad after making several high-profile signings in the summer and has been lauded for having at least two top quality players available for every position.

Yet this is not the case at left-back and it seems Tottenham are determined to make an offer in January for the 28-year-old who is widely considered one of the best defenders in the Premier League.

Everton have shown that they will sell their top players for the right price - as demonstrated by United signing Maroune Fellaini - and they may be forced to listen to offers in January.

While Moyes would be confident his relationship with Baines would make Manchester United the favourites, Tottenham have started the season in superb fashion and are threatening to launch a genuine title challenge.

Baines is contracted until the summer of 2015 and Everton would be confident that they could demand a sizeable fee for the player, should he decide to move on.