Chelsea boss Frank Lampard was delighted with his side's work ethic as Christian Pulisic struck his fourth goal in two games to seal a 2-1 victory at Watford.
The American was on target early in the second period, converting Tammy Abraham's low cross from close range to double the advantage at Vicarage Road.
Despite a late Gerard Deulofeu penalty, the Blues held on to post a club-record seventh successive away win in all competitions.
"Willian takes people out of the game with his pace and I love that Christian scored a goal from four yards out," Lampard added.
"He could have decided not to go the extra mile and that ball flashes across the face and no one gets on the end of it.
"If he continues doing that sort of thing then the goals will rack up. His general performance was top as well."
Deulofeu's spot-kick set up a nervy finale and Chelsea required a massive save from Kepa Arrizabalaga to deny opposite number Ben Foster with the last action of the game.
Foster, who had kept the scoreline respectable with a number of saves, was sent forward for a free-kick and saw his goalbound header kept out by the Spaniard.
"To get a draw would have been an unbelievable turnaround," Foster told the club's official website.
"It was a really good save. I've never scored, and this was the closest I've ever come. Fair play to Kepa, it was a really good save.
"I just closed my eyes and hoped for the best.
"We weren't at our best, I'll be honest. We're close, we know it and we believe it's not far away.
"We didn't get started until 2-0 down. We can't let ourselves get one or two down before getting competitive."
Additional reporting by PA
