However, whether he can begin to produce top form in time to save the Swedish club's sinking Europa League fortunes remains to be seen.
The 27-year-old winger, on loan from Hungarian club Videoton, had been a regular all year until being benched for the season finale against Malmo at the weekend, and he said he could have no complaints given his recent performances.
"This is my worst season ever," he told Swedish newspaper Aftonbladet.
"AIK are a top club and it's been fun to be at AIK and play for the fans, but for me there have been too many lows," he said.
Mutumba could be recalled for Thurday's clash with PSV Eindhoven as AIK try to improve on a dismal run of only one victory in their last six European home matches.
They sit bottom of Group D with only one point from three matches, but perhaps encouragingly, that came last time out from a 1-1 draw away to PSV.
There is also positive news for AIK as they study PSV's growing injury list.
Kevin Strootman is the latest man to head to the treatment room with a back problem.
Strootman had been wearing the captain's armband in the absence of Mark van Bommel, leaving coach Dick Advocaat with a double headache.
Also missing are Ola Toivonen and Jeremain Lens, the latter grabbing the goal against AIK last time out.
However, PSV cannot afford to feel sorry for themselves as their return of four points from three matches leaves them second, only one point above Napoli.