This time he could muster a smile was because the errant arm came from an Orange Emus defender who tried in vain to stop Johnston from scoring with two minutes, 40 seconds left on the clock in their Blowes Clothing Cup match.

And that try helped Bulldogs to a 20-17 win over their fierce rivals, maintained their undefeated record at Ashwood Park and wrapped up the minor premiership.

"I copped a good one across the chops for my trouble," Johnston laughed.

"I was lucky enough to score the try, but there was a lot of good lead up work our forwards did beforehand, it was just nice to be in the right spot to get over."

While it was Johnston's try and Will Oldham's subsequent conversion that sealed the win, Bulldogs' defence played the critical role in denying Emus.

The Orange outfit had the better of possession and spent big minutes camped inside the Bulldogs' 22 in both halves.

But Emus only twice breached Bulldogs' defence and even one of those came Bathurst had been reduced to 14 men following Harry Webber's yellow-carding.

"I think our defence was what did it for us today, it felt like in the first half we didn't touch a lot of ball, but we were just in front at half-time," Johnston said.

"I just think when you play against good teams, you can't afford to give that much ball to them and I think we were lucky. A lot of times they had the opportunity to score a try and it was just through sheer determination someone would get there and stop them."

It was sheer determination which denied Emus the opening try of the contest when TJ Cunynghame swooped on a knock-on in the 11th minute. He looked bound for a length of the field effort, but Ben Sheppeard chased back in cover and dragged him down.

Emus continued to pressure via rolling mauls from line-outs, getting within inches of the line, but Bulldogs held on.

In the 23rd minute when points finally came they were off the boot of Oldham, a penalty goal giving Bulldogs a 3-0 lead.

But it was only temporary respite from the constant phases of Emus' attack. The greens found space through their back line down the right edge on several occasions, but it was a show of strength from hooker Charlie Henley close to the line - ploughing his way over - that finally broke Bulldogs.

Nigel Staniforth converted and it looked as if Emus would carry a 7-3 lead to half-time, but 38 seconds out from the break Bulldogs centre Adam Plummer streaked away down the left flank and Oldham nailed the following kick from the sideline.

Four minutes after play resumed a Staniforth goal locked it up at 10-all and eight minutes later - with Webber serving his yellow card penalty on the sideline - Tom Joseph crossed to give Emus the lead.

An Oldham penalty inched Bulldogs closer, but the momentum was with Emus. The problem for the greens was they could not capitalise - Joseph was held up over the line and when Cunynghame won the race to an in-goal kick, the ball had gone dead before he grounded it.

With 11 minutes left Staniforth was shown a yellow and when Johnston crashed over between the sticks, it handed Bulldogs the lead. After Oldham's conversion there were 91 seconds left and the Bathurst side held on.

Given they had controlled much of the match, it was a tough loss for Emus to swallow. It was the second narrow defeat for the greens at Ashwood Park this year, having gone down 21-15 in round four.

"It was a good game to watch, frustrating at times because a few things didn't go our way, but that's sport, that's life," Emus coach Pete Bromley said.

"They have been three close games, all three of them. We lost by a couple of points here, we won by a couple when they played at Emus and we lost by a couple of points again here.

"There's nothing much between the sides, it's just on the day who can finish the game off and we just ran out of puff at the end.

"It was a good game, both sides were willing and very combative and that's the good part about the footy, it's always a war out there for both sides."