Matt Roller is an assistant editor at ESPNcricinfo. He tweets at @mroller98
Sam Billings was set to carry drinks in England's first ODI of the summer on Thursday, but Joe Denly's back spasms at training the day before the game handed him a rare chance to prove his worth.
Billings has been named in just about every England white-ball squad over the last five years, but opportunities to bed in for a series have been few and far between. When and if he walks to the crease on Saturday, with an unbeaten 67 in the first match guaranteeing him a spot in the XI, it will be the first time since 2017 that he has batted more than once in an ODI series.
"The middle-order role is a very tough one," Billings said. "You've got to be very adept, come in when you're three or four down early on and steady the ship similar to [Thursday] or in the last five overs and everyone expects you to get 40 off 10 balls.
"It's a pretty tough role, but one that I'm looking forward to making my own, really. Morgs [Eoin Morgan] has chucked the challenge out for all of us batsmen. There are a ridiculous number of white-ball batsmen in the one-day set-up at the moment, and I just want to focus, keep working hard, and keep doing what I'm doing."
It might come as a surprise to look at Billings' career record and realise that he has only batted 36 times at international level. He was part of the generation entrusted with turning English white-ball cricket around at the start of the 2015-19 World Cup cycle, playing all five of the ODIs against New Zealand that kickstarted Morgan's project, but with Morgan himself, Jos Buttler and Ben Stokes forming part of a formidable middle order, has struggled for regular playing time.
Billings' former county captain, Rob Key, wondered on Sky if he had "benefitted as much as people think from playing in the various leagues around the world" following his innings on Thursday.
"When he has gone to those, like the IPL, he has carried drinks," Key said. "When he has been picked for England, he has carried drinks, playing the odd game here and there. He has been around for a while, but he hasn't necessarily had a run of games."
"I think he's spot on with that," Billings responded. "You have to be playing cricket whatever team you play in, especially as a batsman. It's very hard to come in for the odd game here or there and hit the ground running.
"In the past I have come in for the odd game here or there and put way too much pressure on myself, [and I've] gone away from what I have done well in the past. It's an opportunity that has come out of an unfortunate situation to one of my best mates but that's sport and at the end of the day, I have got to do what I have got to do."
While his path into England's first-choice ODI side remains unclear - unless Morgan retires before 2023 - Billings is no longer focusing on white-ball cricket alone. He revealed to ESPNcricinfo during lockdown that he retains ambitions of winning a Test cap after twin County Championship hundreds against Yorkshire at the end of last season, and thinks that his ability against spin will put him in contention for a role on a subcontinent tour before long.
Though Billings' international record against spin is actually slightly worse than it is against seam, that is a reflection of the limited opportunities he has had. Across his T20 career, he has scored at a marginally quicker rate against spin, despite generally coming in during the middle overs, and averages more runs per dismissal against slow bowlers.
With the next 50-over World Cup and one of the next two T20 World Cups in India, he is confident that IPL experience will give him every chance of playing. "I think that's something I can potentially offer compared to other players" he said, "benefitting from all the different franchise experiences I have had, but specifically the IPL and the relative success I have had on turning pitches in Chennai and Delhi.
"I back my game against spin and it's definitely something I have got to continue to work hard on. [This] is arguably one of the toughest sports teams to get into as a fringe player at the moment. All I can do is take my opportunities when they arise. Building towards the subcontinent, whether that's the one-day formats or the longer format as well, I think it's somewhere I could potentially do well."
He has made technical adjustments over the winter, too, after taking time away from franchise leagues following a disappointing T20I series in New Zealand. He found himself facing "a bit of a struggle" getting his hands up in time to play short balls from fast bowler after dipping his hands at the bowler's release point, and is trying to stay "dead still" in his stance with his hands going "straight up". He clearly knows his own record inside out - when he cited his List A stats for Kent in his post-match press conference, the only surprise was that he left out the decimal place.
"[My England career] hit a heavy speed bump last year," he said. "For me, it's just about building that momentum back up. It has been very up and down over the last five years. I played those five games against NZ after the last World Cup  and played ten since then, the last being in 2018 in this format.
"For me, the opportunities have been sporadic and like I said, this team is the hardest team to get into. But I have to keep on putting performances on the board when I get the opportunity." In time, he may look back on Denly's injury as his own Sliding Doors moment.