The midfielder joined the Gers at the very start of the January transfer window.
Harry Forrester has revealed that his mind was made up regarding his future as soon as he heard that Rangers were interested, despite attracting attention from English clubs, the Evening Times reports.
The 25-year-old signed a contract with the Gers until the end of the season upon leaving former club Doncaster (via Evening Times), and while Forrester confirmed that he had the chance to stay south of the border, his decision was quickly made once Rangers entered the running for his signature.
"As soon as I found out that Rangers were interested, there was nowhere else I wanted to be," he explained to the Evening Times.
"There were a few teams in England interested, but as soon as I got the call there was nowhere else I was going."
As well as the prospect of joining a club of Rangers' stature, the opportunity to move to Ibrox presented Forrester with the chance to link up with Mark Warburton, for whom he played under during his time at Brentford.
Having fallen out of favour under current Doncaster manager Darren Ferguson, a move to Glasgow should allow Forrester to prove himself. Warburton has already shown during his first few months in the job that he is more than willing to give younger players the chance to form much of the spine of the side that he hopes will end the season by winning the Scottish Championship and returning to the Premiership.