The openside flanker enjoyed a memorable season with Wales and lead the Dragons to a World Cup semi-final and Grand Slam.
But he has struggled with injuries and found increased competition from Ospreys flanker Justin Tipuric, with some pundits even calling for him to be dropped.
But Warburton reckons the competition for places is perfect for Wales.
"I'd be lying if I said I wasn't under pressure, but it is great that we have someone like Justin," Warburton told the Western Mail.
"I played with him in the under-20s and on the sevens circuit and I've seen him come through the Ospreys academy, I knew what a talent he was before anyone else did.
"It didn't surprise me when the Ospreys named him captain because he is a very influential figure, a very professional guy who gets on with everybody.
"He is a great player and it is great for us as a nation to have a lot of competition for places.
"A few years ago people said we had just a strong XV, but now we have a strong 30. Great Welsh players seem to be coming through the system."
Warburton returned to pre-season training with Cardiff Blues last week, following a five-week break.
He admits he needed to mentally switch off from rugby following a rollercoaster year but he was also glad to allow his body to recover from the physical tolls of the game.
"But I've come back to pre-season mentally fresh and, although it gets tougher every year, it has felt pretty good so far.
"I actually feel hungry to play again. Five weeks is enough time off.
"It was a very long season, but in the time I've had off I put my feet up, stayed away from rugby and didn't do anything.
"I reflected on last season and now I'm really motivated for the time ahead.
"When it comes to playing the big Cardiff Blues and Wales games, getting yourself up for them mentally does take quite a bit out of you.
"That is why a break is a great chance to refresh. I got rid of a lot of the niggles I had and my knees, for example, feel better than they have for some time."