As he continues his challenge for one of the unpaid game's biggest prizes, as well as a place in next season's Open Championship, the 20-year-old from Kuopio is also counting down the days until he completes his national service.
"I have four more days to do when I go back," said Ruuska, of a conscription that still remains compulsory in his native land.
A level-par 71, to add to his opening 67, kept him on the straight and narrow at the sharp end of affairs as he finished in a share of the lead with Renato Paratore, Ben Stow and Gary Hurley on a four-under 138.
It's been good shooting so far from Ruuska who seems to be just as handy aiming and firing with a golf club in his hands as he is with a standard issue rifle. "I'm going to shooting camp in the forests and I am quite a good shooter," added the Finn, who highlighted his round yesterday by blasting a 3-wood off the 10th fairway into 15 feet and knocking in the birdie putt. "National service is not so great in the winter. We have to sleep outside with just a sleeping bag when it's minus-15 degrees."
Ruuska is hoping to follow in the trailblazing steps of his countryman Mikko Illonen and forge a successful career on the European Tour. Paratore, meanwhile, has his own compatriot to aspire too in Italian youngster Matteo Manassero.
At just 17, Paratore, the back-marker in the field this week with a handicap of plus 5.8, is making sizeable strides in the right direction and is currently ranked fifth on the world amateur rankings. Like Manassero at a similar age, he also plays the game at a sprightly pace and doesn't descend into the relentless pre-shot plooterings that has made modern golf slower than coastal erosion.
"I always want to go fast and I hate slow play," said the teenager from Rome, who added a 69 to his tally and admitted he will be trying his luck at the European Tour's qualifying school later this year.
While Ruuska ducks and dives about the Finnish woods on a variety of military manoeuvres, Paratore prefers to steer clear of the rough and tumble. "I gave up football and skiing because I was afraid I might break something," he added with a smile.
Stow, the Brabazon Trophy winner earlier this season, birdied two of his first three holes but a double-bogey at the 11th and a leaked shot at the 12th made sure he did not burst away from the pack and his 71 left him in a four-way tie at the top.
Scott Borrowman, the former Scottish amateur No 1, was off in the second group of the day but by the end of it he was still right in the thick of the title tussle as he picked up a pair of birdies on the back nine in a battling 71 that had him lurking just a shot off the lead on 139. "When you're off that early you don't know where you'll be sitting but I'm still in the mix," he said.
Another Scot, Connor Syme, sits on the fringes of the top-10 with a 143 after a 70.