In an innings his teammates rated as one of the finest of his career, Aaron Finch has taken a sledgehammer to the World Cup selection headache Australia is currently nursing.

Hours after David Warner made an impressive return to cricket in the Indian Premier League, Finch followed suit with a mammoth unbeaten 143-ball 153 in Sharjah against Pakistan on Sunday.

It was the Australian captain's second match-winning ton in as many games, helping to pull off two of the three largest run chases in the venue's history.

The struggles of Australia's 50-over side during the bans of Warner and Steve Smith led most to assume the pair will be whisked straight back into the roles they occupied before Cape Town.

Yet breaking up a blossoming opening bond between Finch and Usman Khawaja for the World Cup would now be a huge call.

The pair have posted four centuries between them in Australia's last five games and shared in 60-plus partnerships in five of their last six matches – including stands of 193 against India and then 209 on Sunday evening against Pakistan.

Finch had gone so far as to say he'd be open to batting down the order if it benefited the team after going 30 innings without a ton in any format before Friday's series opener.

But Lyon said his knock from the top against Pakistan in the second one-dayer was as good as he's seen from him, highlighting the role coach Justin Langer and batting mentor Graeme Hick have played.

"It's probably the most controlled innings I've seen him play in a long time," said Lyon. "And hats off to him - he's been working his backside off.

"I know he hasn't probably had the runs over the summer that he would like. But he's been working hard with Graeme Hick and Justin Langer. They've all been absolutely working their backside off.

"A lot of credit has to go to Finchy obviously, but I think ‘JL’ and ‘Hicky’ certainly need a pat on the back as well, they've been absolutely brilliant.

"If you have the support of changeroom, which Aaron certainly does. and you know he's doing the work outside games, you know his turn will come around.

"It's just great to see Finchy cash in. For him to bat the whole innings and chase down 285 and score 153 not out - in my eyes it shows a great leader.

"He deserves every accolade he gets - especially for that innings but hopefully he can take a lot of confidence out of that and the way he's leading this side going into the World Cup."

Finch's 13th ODI hundred was also a reminder of his dominance over an extended period. He moved one closer to Warner's tally of 14 international 50-over tons, with only Ricky Ponting (29 centuries), Mark Waugh (18) and Adam Gilchrist (16) ahead of the pair.

Khawaja's flourishing career in 50-over cricket has been more recent, but on Sunday he passed 1,000 ODI runs in his 27th innings, a historically-impressive mark only bettered by Greg Chappell and George Bailey (both 26 innings) respectively.

The only other member of Australia's top-order who has batted in both games, Shaun Marsh (91 not out and 11 not out), is yet to be dismissed in the series, while Peter Handscomb earnt praise for his role in guiding the visitors home in series opener.

All of which sets up an unenviable dilemma for the selection panel, which will name the World Cup squad next month.

"It's absolutely amazing that our batters are really standing up and scoring big runs," continued Lyon.

"To see (Warner) go out there and score 85 … I really hope Davey and Steve have a fantastic IPL in preparation and that's just going to cause massive headaches for our selectors heading into the World Cup selection.

"I think it's a great problem for Australia to have."

Finch hinted that Australia could field some "different combinations" for the final three games of the series to be played in Abu Dhabi and Dubai.

"(Khawaja) has been in great form over the last few months of one-day cricket in particular. He's getting big runs and at important times," Finch told the host broadcaster.

"Things are going quite well at the moment but you're never satisfied. You're always looking to improve and I think there will be some different combinations at some point throughout this series.

"It's just a great opportunity to keep learning and keep improving with a big few months coming up."