The Merseyside outfit managed to complete a £40m deal to sign the 24-year-old versatile midfielder from their top-six rivals Arsenal.
Oxlade-Chamberlain opted to move to Liverpool FC ahead of signing a new contract with Arsenal or a transfer switch to defending champions Chelsea.
Wenger signed the versatile England international in a £10m deal from Southampton in 2010 when Oxlade-Chamberlain was an unpolished Championship talent.
The Liverpool FC star won three FA Cup titles in four seasons at the north London club during his seven season stay at the Emirates Stadium.
Oxlade-Chamberlain was in the same position as Alexis Sanchez, Mesut Ozil and Jack Wilshere with less than 12 months on his Arsenal deal before his deadline day move to Liverpool FC.
And Wenger confirmed that he wanted to keep Oxlade-Chamberlain at the Emirates Stadium but was powerless to deny the midfielder a summer move to Anfield.
“Look, he had one year to go,” Wenger told a news conference last week. “At the start of the season we had four players with one year to go and I wanted him to extend his contract.
“Yes, he decided to go and we respect that. He made his decision and we had to find a compromise to get the best possible transfer fee.
“I personally think he will be an important player for England and that he will continue to develop.”
Oxlade-Chamberlain has scored two goals and has made two assists in 17 appearances in all competitions in the 2017-18 season so far.
The England star has scored against Maribor and West Ham United in the current campaign.
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