Pierre-Emerick Aubameyang slotted in from inside the six-yard box in the 32nd minute after a pass from Ainsley Maitalnd-Niles capped off a 20 pass move from the Gunners.
Twenty passes were the most in a move leading to a goal in the English top-flight this season, according to Opta.
The Gabon international was involved in the move, passing the ball to Granit Xhaka before setting off on a lung-bursting run. Xhaka found Mesut Ozil, who in turn released Maitland-Niles before the former Dortmund man capped off a move that seemed to bemuse the Hornets.
Aubameyang had opened the scoring in the 21st minute after being found by Sead Kolasinac.
He now has 14 goals in his last 14 appearances for Unai Emery’s men.
It was his 37th goal since joining the Gunners, and allied to his nine assists he now has 46 goal involvements since he swapped the Bundesliga for north London in January of 2018.
In that span only Mohamed Salah of Liverpool has been involved in more Premier League goals than the 30-year-old 59-cap international.
20 - There were 20 passes in the build-up to Pierre-Emerick Aubameyang's second goal for Arsenal against Watford - the longest passing sequence leading to a goal in the 2019-20 Premier League campaign so far. Rhythmic. pic.twitter.com/5yPy0uPmEy— OptaJoe (@OptaJoe) September 15, 2019
Aubameyang has been extremely efficient recently, with Opta reporting that he has banged home seven goals from his last nine shots on target in the top division of English football, including each of his last four.
Watford are favourite opponents of Arsenal as a team and their talismanic forward.
The Gunners have defeated last season’s FA Cup finalists in three consecutive matches, and have kept a clean sheet in each. The Hornets were the only team that didn’t score against them last season, though an error by Sokratis led to Tom Cleverley breaking through for a Watford goal in this clash.
Aubameyang has now been involved in five goals in four games against Watford, with his double today adding to two in previous games, as well as one assist.
The Gunners would fail to hold on, however, as a penalty given away by David Luiz allowed Watford to equalise and snatch a share of the points, though they remain without a win on the season.
Sunday’s game was the first for Quique Sanchez Flores, who returned for a second stint following last weekend’s sacking of Javi Gracia.