Stefano Okaka scored twice for Watford as they beat Everton 3-2 at Vicarage Road.
The former Roma striker, who was making only his second Premier League start of the season, struck either side of a Sebastian Prodl header, after Romelu Lukaku had put the visitors ahead.
Belgium stiker Lukaku, who has almost single-handedly kept his side afloat during a dreadful of run of results that has seen Everton win just once since September, narrowed the deficit late on with a header.
Everton's Romelu Lukaku celebrates scoring their first goal
Image credit: Reuters
But the 23-year-old, who has now scored or assisted 12 of Everton's 19 Premier League goals this season, could not fashion an equaliser and prevent Watford climbing above the Toffees in the table to eighth.
The win is a first for Watford against Everton since March 1987, three months before Prodl, the scorer of the Hornets' second goal, was even born.
Walter Mazzarri's Watford face back-to-back away trips to Manchester City and Sunderland over the next week, while Everton have two home games against Arsenal and Liverpool to come.
Is Everton's defence as poor as it was under Roberto Martinez?
Ronald Koeman made the defence his key priority for improvement when he was appointed as successor to Martinez, and the summer signing of Swansea and Wales captain Ashley Williams was a clear statement of intent. But Everton seem to be easily bullied by strong strikers like the Watford pair of Troy Deeney and Stefano Okaka, while goalkeeper Maarten Stekelenburg struggles to command the space behind his back four.
Koeman will be active in the transfer market in January, with Manchester United's Memphis Depay top of his wishlist, but maybe funds should be targeted on a new goalkeeper and another centre-half?
MAN OF THE MATCH
Stefano Okaka (Watford)
The Italian netted his first Premier League goals since scoring for Fulham against West Ham in May 2010, and the backheeled near-post volley from Nordin Amrabat's cross will definitely be one for the 27-year-old's showreel.
But it was the hunger and desire the four-time capped Azzurri international showed that also caught the eye. Mazzarri likes a high workrate from his forward players, and when he goes back to analyse the match, he will note the moment the TV cameras lingered on Okaka labouring for breath after another run back into midfield to help out Adlene Guedioura, Valon Behrami and Etienne Capoue.
Watford's Sebastian Prodl celebrates scoring their second goal with Troy Deeney
Image credit: Reuters
Everton: Stekelenburg 6, Baines 6, Williams 6, Funes Mori 5, Coleman 6, Barry 7, Gana 7, McCarthy 7, Mirallas 6, Deulofeu 7, Lukaku 7. Subs: Barkley 6, Lennon 7, Valencia 7.
13' – GOAL! Watford 0-1 Everton. Lukaku calmly finishes from a Barry ball over the top, for his eighth goal of the season. That is 13 goals from 15 games for Lukaku, if you include his appearances for Belgium.
36' – GOAL! Watford 1-1 Everton. Okaka volleys a brilliant backheel past Stekelenburg from Amrabat's cross. That is his first goal for Watford, and a contender for goal of the month.
60' – GOAL! Watford 2-1 Everton. Prodl heads home Holebas' brilliant whipped free-kick for his first goal of the season.
64' – GOAL! Watford 3-1 Everton. Okaka outruns Barry at the near post to flick the Holebas corner beyond Stekelenburg.
86' – GOAL! Watford 2-3 Everton. Lukaku gets his second of the match from Lennon's cross. This sets up an intriguing last few minutes! Another header conceded by Watford - no PL team have conceded more this season.
Romelu Lukaku's header was the 10th Watford have conceded in the Premier League this season, a league high.
Ronald Koeman's side have kept only one clean sheet in their last 11 Premier League fixtures, and have had just one win since September, the 2-0 home win over West Ham on 30 October.
With his brace against Watford, Romelu Lukaku has now scored against 22 different Premier League clubs.