This year he is caught up in a battle to keep Kilmarnock in the top flight of Scottish football, a status they have held for 21 unbroken years.
The Rugby Park side head to Tynecastle to face Hearts today knowing that defeat will ensure they remain in the SPFL Premiership play-off place with only two matches left to alter that position.
"I think every manager in the bottom half of the Premiership is under pressure depending on results and I'm no different," said Johnston, who took charge of the Ayrshire club last summer. "It's been a real test but hopefully I'll improve with every year that passes. I knew it was going to be tough because when I came here because we had about half a team and the budget had been significantly reduced. But it has been a hard year for a lot of people; there have been a lot of problems at a few clubs."
At least Kilmarnock's players only have themselves to worry about now, after a hastily-convened SPFL investigation into allegations of falsifying a signature on a player registration document was unable to come up with a case to answer.
Kilmarnock's final league placings over the last 10 years - 10th, sixth, sixth, fifth, 11th, eighth, 11th, sixth, seventh, ninth - are respectable for a club of their size but a disconnect has grown between those who run Kilmarnock and their fanbase which is only now being tackled head-on.
The stepping down of the unpopular Michael Johnston as chairman is one strand of the way forward, forming part of a deal involving haulage tycoon Billy Bowie and former owner Jamie Moffat that should free the club from the debt it has been dogged by since the big-spending Bobby Williamson era.
Another will see an artificial surface laid at Rugby Park. This will require an up-front outlay approaching £500,000 but should pay dividends in years to come. Kilmarnock will no longer have to pay to train at Glasgow University's Garscube Campus and the new pitch will generate revenue. There will also be moves to dovetail the club's impressive youth set-up more closely with the senior squad.
"I think you can see behind the scenes that we are trying to get it right with the youth system and some of the boys coming through," Johnston said. "Just now we are up here and you are not really part of Kilmarnock, are you? You are more a Glasgow club as the players are only really down in Kilmarnock on match days. If they were based there they would be more part of the community."
As to the immediate future, it must bring some comfort that Kilmarnock have won on each of their last six visits to Tynecastle. Johnston's only relegation memories come from when he was a player at Sunderland in 1997, not long after he arrived from Rennes, but suffice to say he doesn't want to relive them.
"We lost 1-0 at Wimbledon and that might have been enough but once we were back in the changing room when we found out Coventry City had won 2-1 at Tottenham to send us down. I'd only been there a couple of months but it was a horrible feeling and I definitely don't want to go through it again.
"I don't think there's much of a gap between the top half of the Championship and the bottom half of the Premiership. That's why you don't want to be involved in the play-off, against a team that has been winning more often than yours has."
Midfielder Sammy Clingan, who has been back in action the last couple of weeks after a knee injury, has the misfortune to be relegated not once but twice from the English Championship to League One, with Norwich City in 2009 and Coventry in 2012. Hibernian's James McPake was a team-mate on both occasions.
"They were two big clubs, no-one expected them to be down there, but we were and we went down," the Northern Irishman said. "It's not a nice thing to have on your cv, I didn't like the feeling and I don't want it to happen again."
"Obviously there are things which have gone on off the pitch this season which the fans haven't been happy with. As players we tried to concentrate on what we get paid for but we haven't had the results this season. The table doesn't lie, at the end of the day. But we still have time."