These two have played together in various national teams several times.
The Sri Lankan player with the shortest name is less obvious. It would appear to be Isiru Udana who has played in a number of ODIs and T20Is over the last decade.
A more likely choice would be Roy Dias of the early Test sides. However, his full name was Roy Luke Dias and the scorecards usually put him down as R.L. Dias.
You can see that the other player’s full name is Isuru Udana Tillakaratna. However, this name does not appear in scorecards or media reports.
Update: Isuru Udana retired from international cricket a few days after this was published.