England picked four debutants – Jordan Cox, Dan Mousley, Jamie Overton and John Turner – for the first ODI and were beaten by eight wickets via the Duckworth-Lewis-Stern method.
Liam Livingstone, standing in as captain for the injured Jos Buttler – another of England’s absent first-choice players – scored a stunning century in the second match to level the series but the tourists were punished in the third match after a top-order collapse left them 24-4.
Phil Salt made a careful and uncharacteristic 74 and Mousley hit his first ODI fifty but their total of 263-8 proved well below par as Keacy Carty and Brandon King stroked centuries for the hosts.
The series defeat follows a 3-2 loss to Australia in September and another away loss against West Indies last winter, which came after their dismal defence of the 50-over world title won in 2019.
Trescothick suggested England have learned more from the series than the results would suggest, name-checking his captain and 21-year-old all-rounder Jacob Bethell, who scored a half-century in the second match of the series.
“We have a better understanding of what our team will look like in comparison to series results,” he said.
“A few guys are really stepping up. Liam Livingstone, for example. Bethell has really shone in the short space of time he has had.
“The support we get is amazing. We have to try and stick with it and understand what we are going through.”