Youngs, 30, began the Six Nations opener in France but was on the bench for the win at Murrayfield.

Head coach Eddie Jones names his team for Sunday's game against Ireland on Friday and Youngs has no ill feelings as he and Heinz compete to start.

"It's not a rivalry," he told BBC Radio 5 Live. "We're working together."

"It's trying to get the best 80 minutes as a half-back pairing and that is what we'll continue to do. We enjoy trying to achieve that for the team.

"I've done it [been on the bench] before and I'm sure I could potentially do it again. Since 2016 when he came in, Eddie has always said it's about the 23. I don't see it any differently. I had a role to play and fulfilled it."

The Leicester scrum-half is one of the most experienced players in the England team, with 97 caps compared to Heinz's 11.

And Youngs admits England will have to mindful of another experienced nine on Sunday - Ireland's Conor Murray.

"I have played against Conor a number of times now," Youngs added.

"He orchestrates the team along with Johnny [Sexton]. They have a great partnership and understanding.

"A lot of what Ireland do in terms of trying to squeeze you tactically with the kicking game comes through Conor so he will be an important guy for us to try and unsettle."

Further front-row uncertainty

Beno Obano played for Bath against Worcester in the Premiership on Saturday

Jones has recalled Bath prop Beno Obano to his training squad as cover for Joe Marler or Ellis Genge.

The 25-year-old was released from training on Wednesday, but could now be in line for his first England cap with loose-head prop Mako Vunipola unavailable after returning to Tonga for family reasons.

"We've got a few niggles so we needed an extra prop in there," Jones said.

But the England coach would not specify whether it is Marler or Genge who is a doubt for the match at Twickenham.

Marler was set to return at loose-head prop, with Genge resuming his role as a replacement.