Danny Care says he has unfinished business with the Rugby World Cup and is "giving it everything" to cap his "rollercoaster" international career at the tournament in France.
After missing out in 2019, Care says it would be a "dream" to make the squad.
"I've never been as determined to get in an England shirt as I am now," he told the Rugby Union Weekly podcast.
"As soon as I spoke to Steve and there was a possibility of coming into camp and fighting for a shirt I jumped at the chance."
The Harlequins veteran won the bulk of his 87 England caps between 2008 and 2018, before being jettisoned by former boss Eddie Jones.
After almost four years in the wilderness, Care won three more caps on last summer's tour of Australia before being left out in the autumn by Jones and then the recent Six Nations by Borthwick.
But when approached about his availability, Care says he did not hesitate to give it another shot.
"Instantly the answer was yes: I would do anything to play for [Steve's] team," he said.
"To play in a World Cup is a dream and I will give it everything. For me anytime an England coach wants you to come in and give it a crack, the answer is always yes.
"It's why I've stayed in England for 18 years as a player, I always wanted to play for my country, it means an awful lot to me.
"I've flown into it and given it everything. I feel as good as I have in years. It's been tough and it's been graft, but it's the World Cup and it has to be. I've loved every minute.
"It's been a rollercoaster, but I wouldn't swap any of it."
'World Cups haven't been what I wanted'
Despite being England's second most-capped scrum-half in history, Care has played just one World Cup game, a dead rubber against Uruguay in 2015.
In 2011 he suffered a serious foot injury when in line to be England's starting nine, in 2015 he was third in the pecking order, while in 2019 he failed to make the training camp.
"World Cups haven't been what I wanted them to be," Care said.
"So I would give anything to get in that 33 to France. The dream is the dream, to do what the '03 lads did and go and win the trophy.
"I've seen it all. I've been there, I've been named in a squad and not been able to make the plane through injury. I've seen lads come from nowhere and make a World Cup.
"Anything could happen, it's rugby. All I am focusing on is each day and trying to work hard and help the team."
And having been in camp for the past three weeks, Care says he is hugely encouraged by the quality of coaches and players at England's disposal.
"As a head coach I have been blown away by [Borthwick's] detail and how he drives the team forward," he said.
"This England team is going to be a very good team. I can assure you of that. There are some frighteningly good young players in this squad that could be brilliant players for England for years."