Buffalo Bills running back Christian Wade made an immediate impact on his NFL debut and the rugby union convert described taking his first carry 65 yards for a touchdown as "the best feeling in the world".

Wade, who was capped by England in his previous sport, made the switch to American football in October and was assigned to the Bills in April as part of the NFL's International Player Pathway Programme. 

The 28-year-old wasted no time in showcasing his ability in Buffalo's first preseason game, as he cut back through a huge gap in the Indianapolis Colts defense from his first touch and accelerated away for a 65-yard score.

However, the formalities after the touchdown did perplex Wade as his colleagues had to inform him to return to the sideline rather than remain on the field for the extra-point attempt.

"I turned around - because I'm so used to the conversion in rugby - I started running back to halfway and getting ready to go again," Wade explained to reporters.

"I was looking around, didn't know what to do, Everyone was celebrating. I was trying to celebrate but thinking about, 'What am I supposed to do next?'.

"Everyone was like, 'Come off the field!'.

"But it was the best feeling in the world to be able to score a touchdown."

That was Wade's only carry, and he failed to reel in a catch, but he was still given the game ball by coach Sean McDermott for his efforts in the 24-16 victory.

Asked whether he thought he was going to do something so special with his first touch, Wade replied: "Not really.

"People were saying to me, 'I feel like you're going to make a break for 60 yards', people were talking about touchdowns, I was like, 'We'll just have to see what happens'.

"I believe in preparing the right way and I know as a team we've been putting a lot of hard work in.

"The thing I've found with football is it's not just one man who has the show. There are a lot of poster boys but it's a whole team effort."

The Bills have a crowded backfield with Wade vying for snaps alongside LeSean McCoy, Frank Gore, T.J. Yeldon and rookie Devin Singletary, though the Briton can still remain on the Bills' roster as an additional practice squad member under the terms of the programme.

"It gives me the motivation to keep going," Wade said of his touchdown.

"It gives me the positive energy that I'm making strides in the right direction. I know I've got loads of work to do."