The defending premiers chalked up win No.1 one of the Twenty20 season minus spinner Mitch Black and marquee player Ben Mitchell.

And Corben says his side lacked intensity in the field and early-season rust ensured they left "maybe 20 runs" out there with the bat.

Still, the maroons managed to get to 3-144 from 20 overs and then restrict the Bulls, too, despite a game-high 70 off 49 balls from Kyle Aubin under lights.

"It was good to start off with a win - that gets us into the finals series with Centennials now having lost both so that's a positive," Corben said.

Rugby Union is the other side in Pool D, and will also progress through to the finals. Cavs and Rugby don't meet up in their final pool game, though, until January 8.

"It was a bit of a rusty performance all round, I think we left runs out there with the bat and then fielding and bowling we just lacked a bit of intensity towards the end of their innings," Corben added.

"It was a massive job to get the win without a marquee and missing Mitch Black, who plays a massive role for us through the middle-to-back overs with the ball.

"Happy to get the win considering I don't think we played our best T20 cricket."

Opening up, Kaleb Cook top scored for Cavs with a run-a-ball 61 while Corben managed 31 striking at 124, while cameos from Harry Pearce (21no off 20) and Wes Lummis (15no off 4) propelled the defending champions to the more than competitive total.

The maroons then started well with the ball and had the Bulls reeling at 3-25 until the Aubin brothers very nearly snuck Centennials home.

Kyle's unbeaten 70 striking at 143 and Blake's more sedate 24 off 30 balls proved the backbone a gritty run chase, but one that ultimately fell short at 4-138.

"Kyle batted really well - he never let the run rate get out of hand for them, but I backed the boys all the way," Corben added.

Molong takes on Orange City next Friday night - the Molong boys must win to sneak into the finals.