Gavin Henson says he has had his eyes opened in his first three training sessions in rugby league as he prepares to make his debut in the 13-man code.

The former Wales and British and Irish Lions fly-half is set to come out of retirement at the age of 39 after switching codes and signing for third-tier part-timers West Wales Raiders for 2021.

The Llanelli-based Raiders are poised to return to action – after a year's absence due to the coronavirus pandemic – in the Betfred Challenge Cup on the weekend of March 20 and Henson will discover his first potential opponents when the first-round draw is made on Thursday.

"I'm very much looking forward to it and I'm looking forward to see who we get in the cup," Henson told the Betfred podcast.

Henson, who won 33 caps with Wales during his career with Ospreys, Bath and Bristol, has not played since being released by Dragons at the end of the 2018-19 season and was beginning to put all his energy into his new pub business until a chance meeting with the Raiders rekindled an old interest in rugby league.

"I've been messing around playing football but missing the contact side," he said. "It's nice to get a ball in my hands.

"So I thought 'go on, I'll give it a go'. I've always watched rugby league and thought it would be quite cool to have a go at.

"Playing at this level, where the commitment is only a Tuesday and Thursday night and playing on a Saturday or Sunday suits me.

"I'm getting a bit older now but hopefully I can get a season or two in, let's wait and see."

Henson admits he was shocked by the intensity of training, even with a League One club, but is determined to get himself fit for the start of the season.

"I had my first session last Tuesday, so three sessions in now and it's pretty tough," he said.

"To be fair I haven't trained for two years so I don't know whether it's a bit of that or that rugby league training is savage.

"I'm a bit behind but I've got about six weeks to a game if I get picked so I'm just working hard to get back in shape now.

"Training is so different to rugby union. I can't get over the contact side of it. It's flat out, it's 100 per cent. Last night I probably made about 30 tackles which is crazy.

"In rugby union I probably made seven or eight on game day. I don't know what's going to happen on game day in rugby league, I'm just trying to get myself ready for it now."

The Raiders, who finished bottom of the table in 2019, announced the signing of Henson in September and followed it up a month later with the capture of former Super League Man of Steel Rangi Chase, who will be his half-back partner.

"Rangi will play on the left and I'll play on the right as first receivers," he said. "We've been doing that in training, I'm really enjoying it and I think it suits me. I'm pretty excited about it to be honest.

"I'm very impressed by Rangi, not just his skill level but his attitude and intensity – he finished a few boys on Tuesday night.

"He's just so full-on in contact, he's 110 per cent, which you don't really see in union. It's very rare you go flat out but every session he's flat out and so are the rest of the boys.

"It's mind blowing but I'm quickly coming to terms with it. It's great for me and my tackle technique and I need to get better as soon as possible. Ready for when I start playing."

Henson, who went on the British and Irish Lions tour to New Zealand in 2005, says he fielded interest from Widnes during the height of his rugby union career and has become an even bigger admirer of rugby league since he began experiencing it.

"To be honest another reason for getting involved in league is that all the coaches I had and admired the most and thought were the best were the rugby league background ones," he said.

"I feel like there's something in this game that I want to explore and already, just three sessions in, I love the way they train.

"The game is so tactical and I didn't realise that from watching it. I just thought it's hit it up for three or four, then have a go and kick.

"But it's so much more tactical and it's opened my mind up quite a bit. It's quite clever and I love the way it's coached. For me I'd like to maybe stay in league and coach in league possibly."