Two goals from Martín Zubimendi either side of a Viktor Gyökeres strike saw Arsenal's summer signings condemn Nottingham Forest to a 3-0 defeat at the Emirates in Ange Postecoglou's first game in charge on Saturday. 

The former Tottenham Hotspur head coach endured a miserable return to north London, days after his Forest appointment in midweek, as his new charges failed to trouble Mikel Arteta's title challengers. 

Zubimendi opened the scoring with a delightful volley that was only marred by a slight deflection on its way past Forest goalkeeper Matz Sels. Eberechi Eze laid on fellow new recruit Gyökeres to double Arsenal's lead shortly after half-time before Zubimendi made sure of the result with a 79th-minute header. 

Worryingly for Arsenal, captain Martin Ødegaard trudged off in the 18th minute after appearing to suffer a recurrence of the shoulder injury he has struggled with in recent weeks. 

Postecoglou failed to win a north London derby during his Spurs tenure and Forest's last victory at Arsenal was 36 years ago. And Postecoglou's new side might have fallen behind after just seven minutes when Mikel Merino -- fresh from a hat trick for Spain -- saw his point-blank effort diverted from danger by Sels.

Arsenal captain Ødegaard lasted only 17 minutes after he fell awkwardly on his right shoulder after inadvertently colliding with teammate Jurriën Timber.

Ødegaard was withdrawn in the first half of Arsenal's last game at the Emirates with a similar injury, and he was visibly upset when he made his way to the touchline to be replaced by Ethan Nwaneri.

Eberechi Eze was handed his first start but it was Noni Madueke on the opposite wing who caught the eye throughout. On the half-hour mark, he danced past Dan Ndoye to the byline only to see his pullback cleared off Timber's toes by Murillo.

But from the resulting corner, Arsenal had their breakthrough. Chris Wood's header from Madueke's inswinger fell to Zubimendi on the centre of the arc, and the Spaniard's thumping volley swerved away from Sels. It marked Zubimendi's first for Arsenal and, though there may have been a deflection off Elliot Anderson, he will have some job to better it.

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On to the second half, and the hosts doubled their advantage inside the first minute. Riccardo Calafiori's ball over the top found Eze, just onside, and his pass across the six-yard box was coolly converted by Gyökeres.

There was a warning sign for Arsenal when Ndoye's cross thudded into Wood's chest with the ball looping over David Raya, who managed to get his fingertips to the ball and turn it on to the crossbar.

Gyökeres came close to doubling his tally when his thunderous effort from Madueke's no-look pass rattled the frame of Sels' goal.

Madueke's move from Chelsea courted a social media backlash from some Arsenal fans but he was Arteta's star performer and received a standing ovation from the Emirates crowd when he was replaced with 12 minutes to go.

Moments later, the home supporters were celebrating a third when Leandro Trossard's first kick from coming off the bench was met by the head of Zubimendi.

Cue the goading of Postecoglou from the Arsenal fans. "You're getting sacked in the morning," they sang, followed by: "Are you Tottenham in disguise?"

Arteta, though, can reflect on a positive afternoon as the Spaniard bids to end Arsenal's runner-up streak and land the club's first title in 22 years.