Arsenal comfortably disposed on Benfica on the first day of the Emirates Cup on Saturday, sparked by two goalscorers who may not be at the club come the end of August.

Theo Walcott - who has been the subject of interest from London rivals West Ham – netted a first half double to put the hosts ahead following Benfica’s Franco Cervi grabbing the Benfica opener. Eduardo Salvio then gave the Portuguese side parity before half time.

Substitute Lisandro Lopez slid the ball into his own goal in the second period to give the Gunners the lead, before another player who has an uncertain future in North London, Olivier Giroud added to the lead with a fourth goal following an excellent Reiss Nelson cross.

An emphatic finish from Alex Iwobi made it a rout after Giroud linked well during the build-up.

After the humbling defeat at the hands of Chelsea in Beijing last week, Arsene Wenger will be happy with the response his team showed after going a goal down early on, his troops performed like a side who were conscious a crucial season is approaching.

Winning the match at a canter, 5-2, Theo Walcott looked particularly sharp as he scored Arsenal’s first two goals with two ruthless finishes.

While new boy, Sead Kolasinac, also impressed from the left with his clever runs and had a hand in both the first two goals.

Elsewhere, youngster Nelson displayed his tenacity and potential as a right wing back, topping off his performance with a fine cross for Giroud on Arsenal’s fourth goal. Similarly, Alex Iwobi bagged a great goal at the end and appeared refocused since dropping off in the second half of last season.

In a grey, cool and rainy north London, this fixture started off like an autumnal league clash rather than a summer friendly, as both teams came out of the traps fast, focused and concentrated.

The first chance came when Walcott clipped a ball towards Giroud in the box whose headed effort was smothered by a surging Benfica keeper. The game’s opening goal followed not long after as the Benfica winger, Franco Cervi, connected with a flick down header to put Portuguese side in the lead.

But Arsenal bounced back well and Kolasinac showed his promise with a little pulled back chip back for Walcott who volleyed in to bring the game back level. The north Londoners then burst into life and minutes later a one-two between Francis Coquelin and Kolasinac ended up with the ball being played to Walcott who tapped in once again for his and Arsenal’s second.

Not before long, though, the game was brought back on level terms when Toto Salvio tapped in from six yards out after the ball rebounded off Per Mertesacker’s legs as the German tried to block an initial shot.

As ever with Arsenal, the game didn’t escape without controversy or drama. Midway through the first half, a fan invaded the pitch and was heading towards the Arsenal dugout before he was intercepted swiftly by several stewards. Wenger had already stepped out of from his seat in anticipation and exchanged words with the intruder as he was being led away. Wenger didn’t reveal exactly what was said but it was a clear indication of tensions at the Emirates.

Seven minutes after the restart, Arsenal regained the lead when a stretching Benfica defender, Lisandro Lopez, turned the ball into his own net as he desperately tried to intercept Walcott’s low cross towards Giroud.

The Gunners didn’t have to wait long for a fourth goal, as Nelson turned on the edge of the box before looping a cross towards Giroud who volleyed into the net. Alex Iwobi then finished off the rout by firing a fizzing shot past the goalkeeper from inside the box.

With 15 minutes to go, Arsenal fans were given a going home present when new record signing Alexandre Lacazette was introduced in a brief cameo role.

On this showing, the big money striker will know if he wants to be on the teamsheet against Leicester City for the season opener he’s going to have to get past Giroud and Walcott first – if they’re still at the club.