As a result, England head to Colwyn Bay two points behind Grand Slam chasing Wales but with a superior points difference, ensuring whoever wins on Friday will be crowd champions.
And Watson cannot wait to play alongside Nowell, his former teammate at Under-18 level.
He said: "I'm really pleased to be back in the mix, I missed the Junior World Championship last summer with a foot injury and I thought that I would miss the Six Nations after getting a knock in the opening game against Scotland.
"So to be back in the side for this one is a credit to the medical guys and I can't wait to get out there.
"It's been two years since we last played with each other - it was against Ireland with the Under-18s back in 2011 - so
I'm looking forward to playing alongside Nowellsy again and hopefully we get some good ball on Friday. He's a quality player."
Wales are unbeaten in this season's competition, while England have lost one [against Ireland], but Watson believes Rob Hunter's side can secure a third Six Nations title in a row in the coach's final match before he heads to Exeter Chiefs to take up the role of forwards coach.
"The game is a sell-out, we know that it won't be an easy place to go, but it's a challenge we're relishing," added Watson.
"The Welsh boys are looking for a Grand Slam and that brings its own pressures so we're just looking to go out there and play as well as we can."