Courtney Lawes says the fierce competition for places in England's starting line-up has forced him to up his game.
The Northampton Saints star has started in his country's last six matches, helping Eddie Jones side to stretch their winning run to 16 games.
Back-to-back victories to kick off the defence of their Six Nations title have kept alive hopes of a second consecutive Grand Slam and Lawes believes the strength in depth at Jones' disposal has brought the best out of him.
Competing with the likes of George Kruis, Maro Itoje and Joe Launchbury, Lawes conceded: "I've had to raise my game.
"Myself and Joe have had our fair share of injuries, but we've put together a good run of games now both internationally and for our club so that makes a massive difference in terms of getting back to the type of form to stay ahead of Maro or Kruis.
"The good thing is, Eddie Jones is going to choose who is in the best form so all you can do is work your hardest.
"I've had to push myself a lot harder in the last year and a half than I have done previously in my career, it's really good for me as I get to see where my potential is and how far I can go."
Having overcome France and Wales, England host Italy at the end of the month.