Ewan was too strong for Delko–Marseille Provence KTM's Brenton Jones, riding for the Lexus of Blackburn All-Stars, and Heinrich Haussler (Bahrain-Merida) at suburban Williamstown, but was out of contention for the series title because of a mechanical issue in race one.
Austrian Marco Haller (Katusha Sport), the race one winner, finished fourth on Thursday to win the men's series for the first time, ahead of Ewan and Haussler.
"We obviously didn’t want to take any risks, we were expecting Caleb to strike again so I wanted to make sure I finished within the ranks," Haller said.
"I kept an eye on Raphael [Frenstein], I also had one eye on the green. I tried to cover everything a little bit but in the end I think it worked out.
"It’s super cool [to be on the honour roll], next year my name will also be there, people will think about me.
"Maybe I’ll be back next year to defend – you never know. Definitely proud I did it. I wasn’t even expecting to win one.
"As I said I had no idea where my shape was so maybe this was an advantage on the first day because I wasn’t on the radar for some guys."
The pace was forced early with Mitchelton-Scott's Luke Durbridge who was riding for the Lexus of Blackburn All-Stars squad and Alex Dowsett (Katusha Sport) relentless at the front, decimating the peloton and denying attacks. Roger Kluge (Lotto Soudal) again did the heavy lifting for team-mate Ewan and chased down all the breaks.
The 2014 champion Jones surprised Ewan by jumping on the penultimate corner, but Ewan had the firepower to get past again and claim the stage win with Haussler trailing.
More to come.