You'd pray for a winger that finds themselves in a one-on-one with Munster Tom Ahern out on the wing.
The Munster website lists the Waterford man as 6ft 9in and just over 18 stone, and he can move like a man half the size.
With such a big frame, the second row had been his assumed home since he came through the Ireland U20 setup and into the Munster senior squad in recent years, until Graham Rowntree had a eurkea moment back in November, moving the 23-year-old back to blindside flanker in a switch that's proven to be an instant hit.
It was a move that nobody saw coming, even though it was hiding in plain sight. He'd last played there at U18 level for his home club Waterpark, but was soon pushed up to lock. He'd even been a full-back years earlier, and has the speed and ball skills that belie his size, while Munster's gameplan plays to that athletic ability.
Having already scored two tries this season playing as a second row, he's added four more to that tally since moving to the back row, three of which have seen him loiter on the wing before being found by Jack Crowley's crossfield kicks.
"I'd be lying if I didn't say I'm loving it out there," he says, when asked how much he's enjoying his role in the Munster attack.
"Honestly, it's the lads in the middle - our two pods in the middle - if they don't give us front-foot ball, it makes it difficult for us on the edges. So thankfully the guys in the middle are giving me opportunities out wide."
Having Ahern (above) loiter on those wings is giving Munster a target to aim for out wide. As seen with his tries against Glasgow and Exeter and Toulon, when he gets the ball in his hands in the open field he's incredibly difficult to stop, six foot and nine inches of elbows and knees.
What started out as an experiment now looks like being for the long-term.
It was clear that Munster have been keen to keep him in the back row in recent weeks. During their injury crisis at second row, the instead moved Gavin Coombes into the second row so they could keep Ahern at six. And while he did move back to lock in last Saturday's win against Toulon, they restructured the roles of their forwards to preserve Ahern's spot on the wing, with O'Mahony instead having to pick up some of the traditional second row duties in open play.
"It really didn't change much for me, I was staying in the role I was doing in the last few weeks. Pete just had to go into midfield a bit more and help the tight forwards out in midfield. For me, it wasn't much of a change, but Pete was in midfield a bit more.
"Obviously there was a bit of a transitional phase there, it took a couple of weeks to get used to it, because there's a habit of trying to go back inside."
And while it means Munster are losing some considerable bulk in the centre of the pitch, Ahern explains that there's method behind the madness.
"For the team, it's better to stay outside because you draw players out there. I have other fellas in the back row who are helping me great, like Pete, Alex Kendellen, Gavin Coombes, Jack O'Donoghue and John Hodnett teaching me that role and they were very helpful.
"We have a couple of guys holding the edges and we're linking in between the backs and the forwards. Obviously, Prendy [attack coach Mike Prendergast] goes through in great detail during the whole week about when we're going to be there and when we're not going to be there. So it's in different areas of the pitch in attack where we're going to be on the edges and we're going to be in the middle.
"I'd be out there if I'm in that role, you'd be out there for most of the attack shape until we get a bit closer to the goalline and we all start funneling into the middle of the field then."
With 12 games under his belt already this season, Ahern is one game short of reaching his previous best 13 appearances in a single campaign, and his firm has led to a a trial in the Irish squad, included as one of three "training panellists" for the Six Nations along with his Munster teammate Oli Jager and Leinster's Sam Prendergast.
And having spent the majority of last season on the sidelines with a shoulder injury, he believes the biggest reason for his good form this season is simply being able to play week-in and week-out.
"I think it's luck. There's a lot of luck involved in it but obviously being through quite a few injuries, you build up that resilience.
"But I think it's a bit of luck week in, week out that the body is thankfully staying pretty healthy. So it's more luck than anything else, to be honest.
"It's nice having a free run from injuries so it's definitely been the best part of my career with Munster. Knock on wood, it keeps going," he added.
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