Didier Drogba came off the bench to net a late brace that gave Galatasaray a 2-1 victory over Arsenal and secured the Emirates Cup.
The Ivory Coast frontman — who left Chelsea after spearheading their 2012 Champions League final victory before a short stint with Shanghai Shenhua in China — converted a soft penalty on 78 minutes before then producing a crisp finish as the Turks secured their second victory of the weekend tournament, having fallen behind to Theo Walcott's first-half curling effort.
Arsenal, who are still chasing a deal for wantaway Liverpool striker Luis Suarez, showed good form in patches, but again had no answer to the 35-year-old, who had been on Arsene Wenger's radar as a youngster at Guingamp.
"We were in control, they didn't look dangerous, but we were not capable of maintaining physically that rhythm and control in the second half and we were punished for it," said Wenger. "We were exhausted in the end, but it was a good preparation."
Arsenal's only summer signing, Yaya Sanogo, a free transfer from Auxerre, was handed a start in attack, while Spain midfielder Santi Cazorla was back in action after extra time off following the Confederations Cup.
Former Gunner Emmanuel Eboue captained Galatasaray.
There was an early chance for France Under-21 striker Sanogo to become an instant cult hero when he collected a loose pass on the edge of the penalty area, but his angled shot was saved by Fernando Muslera.
Wenger felt Sanogo's performance was sound.
"Considering he has only just come back from holiday with only three or four days' training, what he did do is encouraging," said the Arsenal boss.
Arsenal, who came from 2-0 down to draw with Rafa Benitez's Napoli on Saturday, continued to press and had a penalty shout turned down after Aaron Ramsey tumbled.
On 18 minutes, Walcott expertly took down a long ball from the Welshman into the Galatasaray box, but could then only flick it over the keeper and wide.
Former Bolton forward Johan Elmander caused Arsenal some concern with his link-up play, but Arsenal goalkeeper Wojciech Szczesny, making his first appearance of pre-season after injury, was not really tested.
Arsenal took the lead five minutes before half-time when Walcott's curling cross from the left bounced through the six-yard box and dropped into the far corner.
Drogba was introduced for the second half — to some jeers from the home fans, who remembered him as a man who so often tormented Arsenal during his time with Chelsea. Dutch international Wesley Sneijder also came on.
Drogba was straight into the action, fashioning a chance when he turned Per Mertesacker just outside the Arsenal penalty area, but his shot was straight at Szczesny.
Arsenal, who made several expected substitutions, continued to look sharp, with Alex Oxlade-Chamberlain looking to have been tripped in the penalty area before a downward header from Olivier Giroud was well saved.
The Turks threatened also as Szczesny beat away a fierce drive from Sneijder, the former Inter Milan midfielder.
Galatasaray were awarded a penalty on 78 minutes by referee Jon Moss when substitute Ignasi Miquel was adjudged to have pushed over Drogba, with contact looking minimal at best.
The former Chelsea man made no mistake from 12 yards to continue his fine scoring form against the Gunners.
Drogba then won it for Galatasaray when he collected a cross-field ball from Sneijder before cutting inside Mertesacker and drilling his shot past the Arsenal keeper.
Arsenal must now regroup for next weekend's final pre-season friendly against Manchester City in Helsinki, before the action kicks off for real with the visit of Aston Villa on August 17.
Earlier in the day at the Emirates, Porto came from behind to earn a 3-1 victory against Napoli.
Napoli broke the deadlock just minutes before half-time as Goran Pandev converted a penalty, following Fernando’s nudge on the striker inside the box.
However, Porto came out fighting after the break and Nabil Ghilas soon found the equaliser with a neat finish past Napoli’s Rafael in goal, after some good work from Juan Fernando Quintero.
Porto started to look increasingly dangerous and deservedly took the lead when Federico Fernandez turned Silvestre Varela’s cross past his own goalkeeper in the 68th minute. Ten minutes later, Lica made the game safe, finishing from ten yards out after a mistake by Napoli defender Andrea Dossena.
Galatasaray finished the competition with nine points, ahead of FC Porto with six and Arsenal and Napoli with four.
Information from the Press Association was used in this report.