The Mittagong Lions kept their unblemished season alive on Saturday by holding out a courageous Robertson side in a cracking men's first grade clash at Welby.

Emotions ran high as the bitter rivals slugged it out in an absorbing dogfight that threatened to boil over more than once.

But an own goal in the dying minutes delivered a cruel blow to a Robertson side that have now earned the right to be taken seriously in what seemed like a two horse race for the title.

"There's always been a rivalry between these two sides and I think we really stood up today," Robertson co-captain Dan Robinson said.

"It was a very physical clash and it was a great effort from the guys considering we have lost seven players from last year."

Goals were always going to be hard to come by with desperate defence from both sides setting the tone early on.

But a flash of brilliance by Mittagong's Gordon Cole broke the deadlock with the midfielder making a searching 50 metre run downfield to score a stunning opener.

Mittagong was creating more chances but couldn't convert and Robertson made them pay half way through the second term.

After a scramble inside the D, Robo's Anthony Perkins nudged one past Lions' keeper Tim Neven and it was game on.

This seemed to inspire Robertson and for the next ten minutes they were camped inside the attacking zone, peppering the Mittagong defence without success.

But the Lions again came roaring back and blew a host of good chances until a tragic own goal sealed the match.

"Every time we play there is a real rivalry," Mittagong coach Graeme Isedale said.

"We ran out of legs out there a bit today but it's only early in the season."

Best players for Robertson were Scott Denney, Dan Cox and keeper Jason Brittle while Glen Isedale and Gordon Cole starred for the Lions.

In Saturday's other first grade match, defending premiers Bowral showed why they dominate on turf by pounding Burrawang 6-2 at Frensham.