Smart on the sidelines after breaking thumb

The two-time Weissel Medal winner is waiting for further medical advice after picking up the issue late in Gundagai's win over Kangaroos on Saturday.

"It doesn't feel too bad so I don't think it will be a season-ender," Smart said.

"We've got six weeks left in the season so certainly that's my thinking at the moment, depending on what procedure they go with.

"I'll see the surgeon on Friday and hopefully they decide to put a pin in it and with that I could be back pretty soon."

It is in the same hand he broke two seasons ago.

Smart still can't pinpoint how the injury occurred as the Tigers extended their unbeaten start to the season.

"It wasn't an impact thing and I think it must have got twisted somehow and I just felt it pop," he said.

"It felt like it was just popping in and out for the next few minutes. It wasn't overly painful or anything but just really difficult to catch and pass."

The premiership-winning captain-coach has been at fullback this season but Gundagai have the ideal replacement as they prepare to tackle Southcity at Anzac Park on Sunday.

Dane O'Hehir has been impressing in the centres since returning home this season but Smart knows he's more than capable at the back.

"There is a pretty good option there ready to go and as soon as he went there on the weekend he looked like his old self," Smart said.

"You are certainly not going to be losing anything, if anything in terms of that position in particular it is more dangerous.

"We're certainly different players and I'm sure he will kill it like he does wherever he plays."

Smart has been named Group Nine's best while at halfback for the Tigers but hasn't played there since guiding them to the title in 2018.

With Derek Hay coming in at halfback this year, he's played at the back with O'Hehir and Mat Lyons proving lethal in the centres.

So far the Tigers showed it was working.

"A few people might have been questioning it but you don't know until he is put in that position," Smart said.

"The thing with Dane you could really play him in any position on the field as he's just got natural ability and he's big, strong, fast and skillful."

Damian Willis returns to centre while Gundagai have also named Jake Hay on the bench.

The Bulls are coming off their first win of the season and are looking to put themselves in the box seat for finals with another victory.

They are expected to welcome back Cody Hodge and Luke McBeath from the team who downed Junee last week.

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