The international windows can often prove tricky for clubs as they deal with depleted numbers.
Ulster head coach Dan McFarland may have jinxed himself a few weeks ago when he said he stock of forwards was looking healthy enough, and that "touch wood", he wouldn't have to get creative with any team selections for that weekend's United Rugby Championship meeting with Scarlets
In the end, he very nearly had to be creative a week later against Connacht.
If there was one area they couldn't afford an injury it was at hooker. With Rob Herring and Bradley Roberts in international camp, an injury to John Andrew the day before the game saw Declan Moore - recently signed from Munster - jettisoned into the starting team.
And with no other options available, loosehead prop Eric O'Sullivan was handed the 16 jersey, given a bit of throwing practice, and turned into a makeshift hooker. Break glass in case of emergency.
He didn't make it off the bench though, Moore playing the full 80 and scoring a try in the 32-12 bonus point win, but O'Sullivan says he had no fears of being sprung into the action if needed.
"Obviously I'm not a hooker but I got in on captain run’s day and got through the menu with the callers, Al (O'Connor) was good bringing me through the menu.
"On the bench I was quite relaxed, I wasn’t worried about it too much.
"If I got on I was going to have to throw it and it wouldn’t have been the end of the world if I had of thrown one crooked in my opinion.
"It wasn’t worth worrying about because it would have got into my head more so I was trying to stay relaxed,
"You are not used to the timing of guys moving in the lineout so you kind of have to get an appreciation of that and I think when the opposition see a prop throwing their defence is a bit more keen and they are probably a bit smarter as well they just go front and middle and hope you don’t hit the tail so it narrows down your options a bit," he said.
With Roberts released from the Welsh camp, O'Sullivan will likely be back to the day job of loosehead when Ulster return to URC action this weekend, with the leaders away to the Dragons on Sunday afternoon.
However, there's no guarantee his name will be on the teamsheet, with O'Sullivan and his fellow looseheads Jack McGrath and Andrew Warwick seemingly in a timeshare of the number 1 jersey in recent months, particularly since McGrath's return from injury in December.
"I'd love to play every game but it’s probably not realistic when you have such quality in a position," the one-cap Ireland international added.
"It helps having somebody (like Dan McFarland) who has been in there and knows what it feels like. He's technically so good, he loves looking at footage, giving you any information he can and giving feedback. You learn a lot from him like that."
"You’re going to want to give guys opportunities and guys deserve opportunities. If you’re not playing at your best, you expect guys to get shots, it’s very important that you play as well as you can but then just try to keep building on the momentum.
"Ultimately you kind of know regardless of how well you’re playing you might be rotated because there is such quality in the squad."
While the inconsistency of team selections may be frustrating on an individual basis, it seems to be working for Ulster.
In recent seasons the narrative around the province was they their tight five needed to beef up in order for them to compete for silverware late in the season, and while their young, exciting backline have grabbed the headlines in recent months, O'Sullivan feels the heavies up front are more than pulling their weight.
"If you just look at our maul and set-piece it's improved so much, the tight five have a big part to play in that.
"I think we've all improved individually in there but collectively as a team our maul is better, our set-piece is going well, we’re happy with how we’re going.
"It helps having somebody (like Dan McFarland) who has been in there and knows what it feels like. He’s technically so good, he loves looking at footage, giving you any information he can and giving feedback. You learn a lot from him like that.
"It also helps having such good tightheads in the club because ultimately they’re who you learn from. If Marty Moore is doing a job on you on Tuesday at training you have to go have a look at it. You learn most from them because they give you the picture of what you'll face at the weekend. I think having that level of tighthead in your squad, it helps you as a loosehead to learn the craft."
However, once the tight work is doing, the Dublin native's workrate has been the area that he's consistently praised for, with the 26-year-old consistently hitting high numbers of tackles.
And when he gets hold of the ball, he's happy to try and 'light it up".
"I’ve always backed myself to get my hands on the ball and play passes or put guys into space.
"I remember working with Sopes (Dan Soper) in Banbridge, he was big on moving the ball, 'Light it up’ as he likes to call it.
"I think that’s very exciting and as a squad we have the players to do it and that’s what we need to play to."
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