Watford v Chelsea player ratings: Cleverley 7, Dennis 8; Niguez 3, Mount 8

WATFORD RATINGS: Daniel Bachmann, 6 - Beaten emphatically by too free-flowing Chelsea attacks, but he kept his side in the game with a smart save to keep out Hakim Ziyech’s downward header and he commanded his area well to calmly collect some inviting crosses. Getty Images

Kiko Femenia, 7 - Piled on the pressure from the first whistle and he had Marcos Alonso all over the place as he scrapped relentlessly on the right-hand side, and he drew a super save from Mendy when his whipped cross deflected of Cesar Azpilicueta. PA

Craig Cathcart, 6 - Just about managed to scramble away a dangerous cross from the troublesome Mason Mount late in the first half but he ultimately couldn’t handle the Chelsea man despite a steady display. Getty Images

William Troost-Ekong, 6 - Seemed determined to talk himself into a second yellow card in about thirty seconds after crunching into Mason Mount with a late challenge, but much to the relief of his captain he escaped with no further punishment. Did brilliantly to turn away a dangerous pass from Havertz. PA

Adam Masina, 6 - A 10th appearance of the campaign in all competitions for the left-back, but he was left in clear discomfort after picking up an injury. Never nice to see a player go off with a non-impact injury, so fingers crossed he makes a speedy recovery. PA

Imran Louza, 6 - Did well to contain Chelsea in the first half but he was guilty of wasting a couple of chances with ambitious strikes from distance. Getty Images

Emmanuel Dennis, 8 - Unplayable at times. Six goals and five assists now for the Nigerian - a record only bettered by Mohamed Salah. He had the Chelsea defenders on strings all night and he got the reward he deserved when he levelled the scores just before the break. PA

Tom Cleverley, 7 - Had the Hornets buzzing as he pulled the strings in the middle, and like Femenia he caused problems with some penetrating passes into the box. Lost his footing at the pivotal moment when clean through as he looked to round Mendy. Getty Images

Moussa Sissoko, 6 - So close to putting Watford ahead with what would have been a well-deserved goal after he won back possession in the middle before driving through midfield and playing a lovely one-two with Dennis. Mendy was there again though. PA

Joao Pedro, 7 - Excellent. Nearly opened the scoring when his swept effort from the centre of the box was repelled behind by Trevor Chalobah and he caused problems again when he had Azpilicueta in all sorts of trouble with Mendy forced into a point-blank save. Getty Images

Joshua King, 7 - He just never stops running. It was another industrious display from the energetic forward who led the press well from the front and made life unpleasant for Edouard Mendy at every opportunity. PA

SUB: Danny Rose (on for Adam Masina, 12’), 7 - Brought on following a lengthy stoppage in play and gave a good account of himself, including a couple of perfectly-weighted passes to switch the play. Denied a rare goal by a smart save from Mendy but wasted a late corner. PA

SUB: Juraj Kucka (on for Imran Louza, 73’) NR - Forced Mendy into action when his 93rd-minute piledriver was parried by the Chelsea goalkeeper. PA

SUB: Jeremy Ngakia (on for Tom Cleverley, 85’), NR - A natural defender, he was brought on to provide some fresh legs in midfield, but he had little time to make an impact. PA

CHELSEA RATINGS: Edouard Mendy, 8 – Called upon to rescue his side on multiple occasions, including a flying save to beat away a dangerous Femenia cross that was destined for the top corner after flicking off a knee. Probably earned his side the win in the end, Getty Images

Trevoh Chalobah, 7 – Kept his composure with a sliding intervention to stab the ball away to safety after more good work from Watford down the right. Pushed into the middle after the break, but his night ended with disappointment when he picked up a knock. PA

Andreas Christensen, 6 - Not his most comfortable night’s work. He still made one or two important interventions though, and he looked more comfortable after moving across to the right of the back three. PA

Antonio Rudiger, 5 - Looked much more like himself in the second half, but the damage was very nearly done in the first where he lacked any form of composure and was nutmegged by Dennis as Watford deservedly equalised. PA

Cesar Azpilicueta, 6 – One of his more passive displays. He struggled to match the energy of a Watford attacking trio that had plenty of energy and endeavour, and he was withdrawn for the final 20 minutes. Getty Images

Ruben Loftus-Cheek, 6– A passenger in the first half, a vital cog in the second. He battled hard for everything after the break and used his body well to win a couple of priceless free-kicks that relieved the pressure in a couple of vital moments Getty Images

Saul Niguez, 3 - A rare opportunity to impress, but the Spaniard failed to take it, and you suspect he might not get many more after he was replaced at the interval by a fuming Thomas Tuchel. Getty Images

Marcos Alonso, 7 - A testing night for the left-back who was put under unrelenting pressure by the hosts who targeted the Chelsea right. He had a big hand in the opening goal though, and quickly helped alert the officials when a fan was taken ill. PA

Christian Pulisic, 6 - Hardly involved in the first half, but he got through plenty of running in the second and with a bit more luck he might have had a goal to show for his efforts too, but he lost his footing after being played through by Loftus-Cheek. PA

Kai Havertz, 7 - A bright second half from the 22-year-old, who also made a big contribution in the first when he unselfishly put the ball on a plate for Mount when he could have gone for goal himself. Another good night’s work from him. Getty Images

Mason Mount, 8 - The difference. The forward had a hand in both Chelsea goals, opening the scoring before teeing up Ziyech to put his side back in front, and he smacked the post for good measure too. PA

SUB: Thiago Silva (on for Saul Niguez, 45’), 6 - Chelsea just look so much more assured with him in the side and he produced a couple of important clearances to help the Blues over the line. PA

SUB: Hakim Ziyech (on for Trevor Chalobah, 60’), 7 - Match-winner. Not his most glamorous display, but he was sent on to settle the game and that’s exactly what he did with an emphatic strike into the roof of the net. PA

SUB: Romelu Lukaku (on for Cesar Azpilicueta, 70’), 6 - A pretty average 20-minute cameo in truth. Steady, but nothing spectacular.

Chelsea maintained their lead at the top of the Premier League as Hakim Ziyech came off the bench to secure a hard-fought 2-1 victory at Watford on Wednesday.

Thomas Tuchel's side were not at their best at Vicarage Road but had enough attacking quality to emerge with three important points and stay ahead of Manchester City and Liverpool.

After a 32-minute suspension while a fan was treated for a medical emergency, Chelsea took the lead when Mason Mount coolly converted after a well-worked move in the 29th minute.

But Watford deservedly levelled before the break through Nigerian Emmanuel Dennis.

Ziyech came on for injured defender Trevoh Chalobah on the hour and struck the winner 12 minutes later with the outstanding Mount turning provider.

Chelsea lead the standings with 33 points from 14 games, with City on 32 and Liverpool on 31.

Claudio Ranieri's side will take heart from the way they pushed the league leaders but are just one place and three points above the relegation zone.

Tuchel made six changes from the side that drew with Manchester United at the weekend and Chelsea looked disjointed for much of the evening.

Watford were the better team either side of the suspension but fell behind to Chelsea's first move of quality.

The ball was played to Marcos Alonso down the left and he slipped the ball into Kai Havertz who shifted it across to the unmarked Mount who had time to pick his spot.

Watford responded well and equalised when Moussa Sissoko powered forward and played in Dennis whose shot took a deflection on its way past Edouard Mendy.

The hosts could have been ahead with Mendy making a fine save and Sissoko scuffing a decent opportunity.

The quality on Chelsea's bench eventually told, however, as Ziyech came on to secure the points.

Mount was played into space down the left and his low cross was met by Ziyech whose powerful first-time shot beat Watford keeper Daniel Bachmann for pace.