The 37-year-old was confirmed as a Rovers player on Saturday, signing a deal until the end of the season with the League Two club.
The former Villa man has been training with the club for several weeks and has done enough to earn himself a contract.
Whelan spent two seasons at Villa between 2017 and 2019, being part of the squad that earned promotion back to the Premier League.
He has since had spells with Hearts and Fleetwood Town before becoming a free agent at the end of the season.