GPS I coach Greg Thompson believes his side will start as underdogs in Tuesday evening’s annual representative clash against CAS.  While GPS have traditionally dominated the fixture, that doubles as a selection trial for the NSW Schoolboy teams, CAS has won the previous two clashes over their rivals.  “CAS came out and gave it to the GPS boys in the last two clashes so we’re hoping to turn that around this year, but based on form, you’d have to say we’re the underdogs,” Thompson told Rugby News.  “It’s a new squad and we’ve got a new coaching group this year as well, so it’s difficult to look too much at those past losses.  “In saying that though, there’s generally a sense that the CAS boys have been really up for this match over the last few years and we’ll need to match their intensity to give ourselves a shot.” Four GPS representative sides were selected following the completion of round two over the weekend, with Joeys and Scots both r