Watford have beaten off a host of clubs to sign M’Baye Niang from Milan on an initial six-month deal. West Ham United, Everton, Burnley and Genoa were among the clubs interested in acquiring the mercurial 22-year-old but Walter Mazzarri was able to convince him to move to Vicarage Road until the end of the season.

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The agreement with Milan also includes an option to buy the player for £13.5m in the summer, which is optional unless he plays a certain amount of matches. If he reaches that number, then Watford will have to sign the French-born forward for the agreed fee. The player first wanted a permanent deal straight away but agreed to a temporary switch after talks on Thursday.

Niang is one of the most talented players of his age group but has stalled at Milan. This season he has scored three goals in 18 Serie A appearances and fallen out with the Milan coach, Vincenzo Montella. Montella said this week: “He’s a player who has had his ups and downs and there are things he needs to improve. We tried, and we got to a point where we were delighted with the results – the boy was, too – and I’m not talking about technical results.

“He got to a certain point and then stopped, and I won’t pretend to know why, nor do I want to say. I didn’t like the attitude that he showed when he came on against Torino, and he acknowledged that. He’s done more in the past, as he would also admit. If he stays here, we’ll try again. If he goes elsewhere then I hope he succeeds.”

Niang had a superb spell on loan at Genoa in 2015 when he scored five goals in 14 league games but turned down an offer to join the Serie A side again. Burnley also made a concrete offer but the former French Under-21 forward had his heart set on London and Watford.

Walter Mazzarri’s side have also completed the signing of the Argentinian forward Mauro Zárate from Fiorentina. The 29-year-old has signed a two-and-a-half-year deal from the Serie A team, where he has scored four goals in nine starts this season.

The much-travelled forward began his career at Argentinian side Velez Sarsfield before joining Al-Sadd in Qatar. Zárate went on to make a loan move to Birmingham in 2008 before spending five years with Lazio, helping the Biancocelesti win the Coppa Italia in 2009.

He briefly joined Inter before returning to his homeland to play for his first club Velez. The former Argentina Under-20 international joined West Ham in 2014 and spent a brief period with QPR. The 29-year-old then sealed a move to Fiorentina at the start of the 2016-17 campaign.