Italian Vosawai made a big impact at the start of the season following his arrival from fellow GUINNESS PRO12 side Benetton Treviso.
However a combination of a knock to his neck and concerns over his fitness as well as the form of fellow No.8 Josh Navidi saw him lose his spot in the starting line-up.
In a bid to put himself back in the frame, the 31-year-old has been undergoing an intense fitness program.
And with a try-scoring performance off the bench against Leinster last weekend, Vosawai believes the hard work is starting to pay off.
"After the Munster game at the beginning of November, I had a knock on my left shoulder, with my neck, and I was suffering from a pinched nerve," he told WalesOnline.
"It slowed me down and I really couldn't do much. I couldn't go into contact at 100 per cent.
"Unfortunately my fitness suffered as well from that. There were some issues about that, so the staff here have been making me work hard every week to get back to the level I need.
"When the boys had a day off, I would come in and run, run, run. I have been dying on the field in training, but I am now happier with my contribution to the team physically.
"It's not about losing weight, it's about me to be able to carry my weight, for me to get two or three consecutive times. Before, it was one run and rest.
"I am happy we are sorting that and hopefully in the next couple of weeks I will be completely to another level. We are on the right track.
"I was happy I was able to go out there on the weekend and show I am getting better on those issues."
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