Johnson was having a kick with former Bulldogs' champion Chris Grant when veteran property steward Noel Kinniburgh ran into him with the club's motorised drinks cart.
The cart hit Johnson in the left calf, which was the one that kept him from playing any of the Dogs' pre-season matches.
Johnson left the field after fearing the impact had affected the previously injured area but was soon able to joke about the incident when it was revealed he suffered no new damage.
"People were distracting Noel a bit and Johnno just walked in front of the golf cart just as someone was yelling for Noel to bring the drinks out," coach Rodney Eade told westernbulldogs.com.au afterwards.
"He's started up and clipped Johnno in the lower calf.
"He didn't have any speed up though and it was quite funny in the end. It was serious to start with but he's OK and there's no drama with it.
"There are no repercussions even though some people were worried about it initially."
Johnson had spent the morning boxing, swimming and cycling after feeling overall soreness from his first game for the year on the weekend.
Eade said the accident would not have a bearing on Johnson's availability for this weekend.
"He's fine and was always expected to play this week," Eade said.
"He'll train on Friday and he'll be fine."
Kinniburgh, who has been at the club since the 1960s, has been the centre of jokes since the morning incident.
"We've been telling Noel he's like Lewis Hamilton and that he's ended the career of Johnno and he won't play another game in his life," Eade laughed.
"Poor Noel is getting a bit about it. He's been feeling terrible and the players have been relentless in getting into him.
"But he's a fairly resilient character. He'll be fine, and so will Johnno."
