The Sunwolves may have opened their 2018 Super Rugby season with a loss Saturday at Prince Chichibu Memorial Rugby Ground, but there was plenty in their 32-25 defeat to the Brumbies to show they are going to be competitive in the Australian Conference.

Willie Britz, Kazuki Himeno and Lappies Labuschagne battled tirelessly up front, while Lomano Lemeki and Hosea Saumaki made their presence felt on the wings as Jamie Joseph's side defied its limited build-up.

"There are a lot of disappointed faces in the changing room but I am really proud of the team," Joseph said.

Captain Yutaka Nagare said the Sunwolves had "let the Brumbies off the hook," but said the game had been a "fruitful experience" with the attacking mindset a real positive.

Two tries shortly after the break — one highly fortuitous — eventually proved to be the game changer after the Sunwolves had gone into the break 19-15 up. Joseph's side can take some satisfaction from taking a bonus point off the two-time Super Rugby champions by virtue of losing by seven points or less.

"The feeling is one of relief. We were challenged by a very good Sunwolves side," said Brumbies coach Dan McKellar. "But we showed resilience and worked hard to grind out a win in a tough environment."

Following an early penalty by Christian Lealiifano, the Sunwolves struck twice in the space of 10 minutes through Saumaki and Timothy Lafaele to go 14-3 up.

Saumaki was to add a second as the Sunwolves took the game to the visitors, keeping ball in hand and exploiting weaknesses in the Brumbies' defense.

But the inability of the Sunwolves to clear their own line and their tendency to give up penalties at crucial times was exploited.