Celtic boss Deila has won over stinging critic Hartson
John Hartson admits he has performed a U-turn after watching Celtic speed away from title rivals Aberdeen, declaring: "I'm on the Ronny Deila bus."
The ex-Parkhead striker did not hold back with his stinging criticism of the Norwegian earlier this season as Deila toiled through his first few weeks in the job.
He even claimed the 39-year-old former Stromsgodset boss "did not have a clue" after watching his new Hoops crash out of the Champions League twice before losing at home to Hamilton for the first time in 76 years.
But Hartson - three times an SPL winner with the Glasgow giants - has been impressed with Celtic's recent response.
And he claims they are now motoring towards a domestic treble after moving six points clear at the top of the Premiership with Sunday's 4-0 thrashing of the Dons.
Speaking at the launch of the John Hartson Foundation's charity golf day, the former Arsenal and West Ham hitman said: "At the start of the season there was a few of us, myself included, who were quite critical of Ronny.
"I wasn't alone in that. The fans were having a go, so were the media and I'm sure the board was asking questions too.
"There was lots to be concerned about. They lost 6-1 to Legia Warsaw over two legs in the Champions League but got a reprieve, then lost again to Maribor. There was also the defeat at home to Hamilton in October.
"But now, I'm wise enough to see he has turned it around - and now I'm on the Ronny Deila bus.
"He has brought in fresh legs and impetus with the signing of Stuart Armstrong and Gary Mackay-Steven. Defensively, they look very strong with Jason Denayer and Virgil van Dijk in the middle.
"He's got plenty of options up front and they look a really good outfit now. You would be a brave man now to bet against them winning the treble."