Robin van Persie netted the goal which won Arsenal the Amsterdam Tournament - but was then carried off against Ajax.
A match which was a physical, and often bad-tempered affair, was settled by finish from the Dutchman with just three minutes left.
However, the former Feyenoord player then had to be helped from the field following a heavy challenge from Johnny Heitinga, but was able to soon rejoin his team-mates as they celebrated a second pre-season tournament win.
Manager Arsene Wenger had made some 10 changes from the side which beat Lazio on Thursday, and will have been happy enough with a determined performance.
However, although there were plenty of plus points, Wenger will be hoping Van Persie - clearly the Gunners' main goal threat - does not spend any more time on the treatment table following the extra attention he is bound to receive from defenders next season.
Midfielder Cesc Fabregas was a late withdrawal because of a throat infection, so Brazil teenager Denilson came into the starting XI.
However, there was no place for summer signing Eduardo da Silva, as Alexander Hleb was handed an advanced role just behind van Persie.
It looked a useful tactic as Arsenal enjoyed the best of the opening exchanges.
However, keeper Maarten Stekelenburg was in fine form, somehow producing a reflex save to deny Kolo Toure from point-blank range following a deep free-kick from the right.
The home side made a change in the 24th minute when defender Gregory van der Wiel was replaced by former Charlton winger Dennis Rommedahl.
The Dane almost had an instant impact when he cut inside from the left and flashed a rising drive just over the crossbar.
Van Persie was getting some rough treatment from the Ajax defence, and showed a lack of control when his late challenged earned a caution - and he then took a risk with a sarcastic hand-clap towards the referee, which went unpunished.
Van Persie - who missed the final four months of last season with a broken metatarsal - was in the thick of things as the half-hour mark approached, showing quick feet to nip into the right side of the area and cut the ball back across goal.
There was a warning for keeper Jens Lehmann, though, on 34 minutes when Hedwiges Maduro tried his luck from 25 yards and almost found the top corner.
The match certainly had an edge to it, with William Gallas the next man to be cautioned for a tackle from behind on Klaas Huntelaar.
Wesley Sneijder was on target with the resulting free-kick, but Lehmann got down well to his right.
On the hour mark, tempers - which had been rising throughout the game - boiled over when Thomas Vermaelen appeared to catch Van Persie with a leading elbow as the pair jumped.
Following a brief display of chest-barging, calm was swiftly restored and the referee took no further action.
Eduardo replaced Rosicky, and Hleb moved out wide as Arsenal went with two up front.
Jurgen Collin was very fortunate to escape a red card when he needlessly slid in from behind on Clichy.
Van Persie carved out an opening with 16 minutes left when he picked up the ball on the edge of the area following a strong run from Eboue.
The Dutchman showed great close control to sidestep his marker and drilled a low shot towards the left corner - only for Stekelenburg to make another brilliant save.
Huntelaar saw his close-range header skim the crossbar, but with just three minutes left, Van Persie won it for the Gunners.
A brilliant run from Clichy down the left - started in his own half - took the full-back to the edge of the Ajax area.
He slipped in Van Persie, who made no mistake to drill the ball past Stekelenburg at the near post.
The celebrations looked to have been marred, however, when Van Persie was stretchered off down the tunnel, but the man-of-the-moment was quickly back on the pitch to rejoin the squad for the trophy presentation.
Arsene Wenger was less than impressed with the physical edge to Arsenal's final pre-season friendly, but more than happy with the 'perfect' ending and victory in the Amsterdam Tournament.
'Physically it was a tough game. What you can see is the spirit is strong in the team and that everybody works for each other. That is very positive,' Wenger told Sky Sports 2.
'It has been a perfect pre-season to start the championship.'
However, the Arsenal manager continued: 'I was very disappointed with some of the challenges. I think some players were a little bit overboard, but we kept our nerve.
'Some ways, the fact that you know you would be suspended in England if you over-react here helps us.
'I am proud of them because you cannot let everybody kick you without showing that the team is ready to respond. There was no over-reaction.'
Van Persie is likely to be closely monitored ahead of the clash with Fulham on Sunday following a crunching challenge from his Holland team-mate John Heitinga.
Wenger said: 'I was very disappointed by this tackle, but he looks all right at the moment.'
The Arsenal manager has yet to extend his own contract with the Gunners.
The board are, understandably, keen to get a new deal sorted sooner rather than later.
'I will come out at the right moment, do not worry about that,' said Wenger, who answered 'yes' when pressed as to whether talks were taking place.
The Gunners boss, meanwhile, maintained he was not dormant in the transfer market, but sees no reason to panic buy ahead of the August 31 deadline.
Wenger said: 'I am not sleeping. However, today we had Gilberto out in midfield, [Alex] Song, [Abou] Diaby and [Cesc] Fabregas did not play.
'So we have plenty of quality players, and the pre-season tells you that we have a big squad.'