Salomon Rondon's 29th-minute header, his fifth league goal of the season, appeared to have been enough for Newcastle to complete a league double over Watford.

Watford had scarcely provided a threat in response, but a rare moment of quality eight minutes from time was rewarded as Doucoure's thumping header from Gerard Deulofeu's cross earned a share of the spoils.

Newcastle was eight points clear of the bottom three at one point in the match, but its late collapse and Fulham's last-gasp win over Huddersfield Town means it is only four points above safety after taking just two points from three games.

As he has so often done this season, Martin Dubravka came to Newcastle's rescue to deny Deulofeu with a strong save early on as the former Barcelona forward threatened to inject life into a dreary start to proceedings.

Newcastle had offered precious little in attack but its first promising move resulted in the opener as Christian Atsu found Matt Ritchie, whose teasing left-wing cross was powered home by Rondon as he beat Adam Masina to the ball to head in.

Rondon had the ball in the net again, but from an offside position, before Isaac Success stung the palms of Dubravka at the other end.

An injury to Federico Fernandez suffered in the waning moments of the first half forced Newcastle boss Rafael Benitez to replace the centre-back with Fabian Schar, but the visitors continued in the ascendancy and Rondon headed a Ritchie corner narrowly over.

Newcastle sat back to protect its lead in the closing stages, but could not hang on as a marvellous right-wing delivery from Deulofeu was brilliantly turned home by Doucoure.