'Added street smarts' - Big job for Leeds United's Junior Firpo as Watford dangerman Ismaïla Sarr returns to the Premier League tougher and smarter

The 23-year-old arrived in England from France, where he spent a year with Metz and two with Stade Rennais, who paid around €17m for the winger's services.

The goals and assists he contributed in Ligue 1 and the Europa League, in which he hit the net four times and set up three goals in just nine games, attracted the attention of the Hornets and led to a £30m move.

His first season in the Premier League brought five goals and six assists but Watford finished second bottom and fell into the Championship, just as Leeds escaped it.

Watford Observer writer Ryan Gray believes the relegation has benefitted Sarr, who scored the goal against Millwall that sealed promotion back to the top flight in April.

"I think the year in the Championship has actually really helped him toughen up," said Gray.

"When he first arrived he was raw, but lacked a bit of the strength needed at this level, but a load of games against Championship defenders has really taught him how to play in England.

"He's naturally a very gifted player anyway and he's still very young so is likely going to get better, but I think he has added street smarts now and knows how to get the better of players who perhaps could have marked him out of the game in previous seasons."

The man tasked with keeping him quiet at Elland Road on Saturday will be Junior Firpo - Sarr has played centrally and on the left on occasion for Watford in the past but has operated exclusively on the right wing this season. It will be quite the test for Firpo, whose ability in one v one defensive situations came under scrutiny long before he arrived in Leeds, although his athleticism should at least allow him to match the winger if he stays close enough. The problems for Leeds might arise when Firpo is found elsewhere.

Against Newcastle last weekend Sarr showed how dangerous he can be running at pace off the right flank into the middle, when he is afforded space in which to operate. Leeds have been too open at times this season after turning over possession and Firpo has been caught high upfield due to the offensive duties he carries as a full-back for Marcelo Bielsa. Whoever plays left wing, out of Jack Harrison and Daniel James, will need to work back in support of the former Barcelona man, against a player who once turned down a Nou Camp move.

The goal Sarr scored against the Magpies was a header from a corner, when he was left completely unmarked, but he could have added a second on a counter attack, again running into space this time on the right flank before firing high and wide.

In the game before that, against Norwich, Watford repeatedly looked to get Sarr either into space inside the full-back or in a footrace on the outside, which led to a number of chances. His first goal, however, came when he pulled to the centre to open up space out wide that Watford exploited, before he darted to the near post to convert a low cross. His second came from calamitous Norwich defending and a generous rebound he was able to slot away.

Gray highlights the lack of creativity coming from Watford's midfield so far this season, but getting Sarr on the ball in space leads to danger as the numerous low crosses he flashed into and through the Norwich area proved. The key for Leeds will be to keep the ball away from him in the first place and then restrict his room to manoeuvre when he does get it.