Eoin Morgan says one reason England have to rotate players is the lack of a quality domestic Twenty20 competition.
Jos Buttler and Joe Root missed the win over Pakistan as England attempted to expose more of their squad to pressure situations before the 2016 World T20.
"We don't have a good enough tournament for guys to be exposed to it as often as we'd like," said captain Morgan.
"This is a good tour to expose as many guys as we can to it. If it means senior guys sit out, so be it."
The omission of Buttler, in particular, was surprising after he hit a 46-ball century on the same Dubai ground in the final one-day international against the same opponents last week.
However, his replacement Sam Billings hit a 23-ball half-century to lead England to a 14-run victory and a 1-0 lead in the three-match series.
"We're trying to expand the squad as much as we can," added batsman Morgan, who has spent time playing domestic Twenty20 cricket in both India and Australia.
"For the benefit long term, we'll probably see that more so throughout the series."
Root's replacement, James Vince, also impressed with 41 on debut to help England from 19-3 to a total of 160-5.
Fast bowler Liam Plunkett, in his first appearance of the tour despite having been in both the Test and ODI squads, took 3-21.
"James Vince coming in on his debut to play the way he did on a wicket that the three before struggled to adjust to was outstanding," said Morgan. "That will give him a lot of confidence.
Of Plunkett, he added: "Within the Twenty20 squad, there is a position available for a quick bowler. To come out and do it - when he's only had one opportunity - was brilliant."