It was the first goal Arsenal had conceded since Boxing Day.
The ex-Germany worldwide had been on Arsenal's books since 2013, scoring 44 goals in 254 appearances while getting his hands on three FA Cups, but had not played for the club since March previous year.
"I'd like to thank the club for this wonderful journey over the past seven-and-a-half years", Ozil said Sunday.
Arsenal did not include Mesut Ozil in the Premier League and UEFA Europa League squads for this season and it looks like that was too much for the German global as he opted to leave in this January transfer window to go to Fenerbahce to start playing football again.
One of the standout ties in the fourth round of the FA Cup will take place at St Mary's this afternoon as Southampton welcome fellow Premier League club Arsenal.
"Every German-Turkish person supports a Turkish team when they grow up in Germany", he said.
The former Arsenal star wrote an open letter to supporters after leaving Emirates Stadium detailing how he will always support the club and look back on his time in the Premier League fondly.
Ozil, who was in the final six months of his Arsenal contract, was also linked with a move to MLS side D.C. United as well as clubs in Asia and Qatar.
"Mesut's achievements at Arsenal are undisputed", Arteta said.
"Talks are ongoing with Real Madrid over a deal for the attacking midfielder and Goal can confirm that the north London club are growing in their belief that they are on course to land their man until the end of the season. The biggest club in the country".
'There's been an upturn in fortunes for Arsenal recently but most of the players involved in that weren't involved today, ' he said.
"The way Arsenal play will fit him well, a kind of football that suits him", he told Norwegian media outlet VG. Mesut was at the heart of many great moments for this club over the years, including those three FA Cup final wins.
"He's always part of our sessions, he knows what we have to do", he said. "We thank Mesut and wish him all the best with Fenerbahce".