The England midfielder suffered a dip in performance, which coincided with Arsenal's slide in form last month. But Rice is now getting back to his old self, which has helped Arsenal's recent return to form.
Winterburn told Tribalfootball.com: "I think Declan has played a number of different roles in the team so far this season due to injuries and the red card versus Brighton didn't help.
"But you are only as good as the players around you and some of their stats had probably dropped since last season. The injuries, the change in personnel has also been a factor here for sure and the red cards, means you are then on the back foot.
"But Declan's commitment is 100%, every game, you can see that, he is up and down the pitch, covering every blade of grass. He is one of the players you want in your side and I can see him improving as the season goes on."
Meanwhile, Winterburn was also happy to discuss former teammate Martin Keown, who has just released his memoirs. The pair were part of an outstanding back four at Arsenal and won the Premier League together.
Winterburn said, "I got on well with him. He is a very intense guy, highly competitive, he can come across serious, but that is his dedication, he is very thorough in everything he does.
"It shows he likes me as I have a signed book here with me and I look forward to reading it very soon.
"He was a terrific player, such a hard worker, he had the respect of his peers.
"He wanted to win so much and you could see that in every aspect of his game and the way he conducted himself. You only need to look at his dedication to punditry now, he knows his stuff, he is confident and articulate."
On Keown's arrival from Everton, where he "disrupted" the famous back four of Lee Dixon, Tony Adams, Steve Bould and Winterburn, Nigel adds: "Martin earnt the respect straight away. He was a quality player and he added to our back four he was an extra dimension to what we had and it benefited us.
"Tony and Bouldy were the centre backs, but Martin was massive part of the back four across a number of years."
- Nigel Winterburn was speaking to Tribalfootball.com on behalf of FC25 boosting