It's a question most followers of the A-League Men were asking when, after Nick Montgomery left for Scottish club Hibernian last September, the Central Coast Mariners unveiled Jackson as his replacement.
Jackson's appointment was out of left field.
The Yorkshireman had never coached in Australia, had only recently been sacked by MK Dons following their relegation to England's fourth tier, and his entire playing career had been spent in the lower leagues of English football.
If it weren't for the 46-year-old crossing paths with Montgomery on a coaching seminar - and a stubborn goal frame at Burton Albion in his last game with MK Dons - Jackson might not have made it to Gosford.
"Did I think I'd be going over to Australia? No, but when you're in a position where you're not working you've got to listen to every opportunity," Jackson told AAP.
"(At MK Dons) we were inches away from staying up.
"We drew 0-0 in the last game of the season, had 33 shots, dominated all the stats, ball cleared off the goal line, hit the post. If a goal goes in it would have been different, but these things happen for a reason.
"I knew that I had to change how I approach things - a hard thing for me was understanding when you have to relinquish control."
Nine months on, there can be few left questioning Jackson's credentials.
Following his arrival at Gosford and, after initially encountering some tough results, things have only gone one way: up.
Mark Jackson (centre) has made a huge impression since being appointed coach of the Mariners. (Morgan Hancock/AAP PHOTOS)
The Mariners have sealed an A-League Men premiership, the AFC Cup and can add a second straight championship with a win over Melbourne Victory in Saturday's grand final.
"I want to help build the club and help make the club sustainable and successful," Jackson said.
Before taking the plunge into first-team management, Jackson had spent time at Leeds United working under Marcelo Bielsa.
The Argentine - affectionately known as "El Loco'', or "the madman" - showed Jackson the dedication it takes to make it as a manager.
"We had to align with how he played," Jackson said.
"I was in a privileged position where I don't think there was any other English coach who had been that close to him.
"(Bielsa and successor Jesse Marsch) were extremes of football and personality and you subconsciously take a lot from people without knowing it.
"You look at what they did well and then sprinkle your personality through it."
Jackson has done that to great effect this year and stands just 90 minutes from a historic treble.
His venture to take a job on the other side of the world may have been seen as a gamble, but it's close to being the perfect pay-off.
"We're fighting every day to be successful and we're really pleased with how the season has gone," Jackson said.
"The success we've had mirrors the work from the staff and the players.
"Everybody's been pulling in the same direction and working towards that shared goal."
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