West Brom finally conjured up a reunion with 'Magic Mikey'

The only real certainty, or as close as you can get, is that he was departing his boyhood Celtic for good after 16 of his 25 years on the planet.

The summer effectively started on May 17 and a brief conversation with Carlos Corberan at the front of the team bus that night after Albion’s play-off defeat at St Mary’s.

The winger went away on holiday, stayed in touch with close Albion pal John Swift, as well as Alex Mowatt, Jayson Molumby and Jed Wallace, among others. He had an inkling a move away from Parkhead could run late – and that was how things played out.

Corberan last week revealed Johnston had made his permanent Baggies intentions very clear after play-off heartache. Deep down, though, the Republic of Ireland international felt an offer from Albion would be tough to manoeuvre, as did the head coach.

“It was on the bus after, he called me to the front and said if there was anything they could do to bring me back then they would do and straight away,” Johnston says.

“It makes you feel wanted and that’s all a player ever really wants, to be honest.

“I thought it was kind of an outside chance, to be honest. You hear all things about FFP (financial fair play) or whatever, I don’t know the ins and outs, it was the summer and I knew I was probably leaving Celtic.

“With the options I had it was going to go on until the last day, Celtic were wanting to make sure it was round about the end that I left and that gave West Brom every chance to come in and match other offers that were in.

“When they did that and the options were in the same league, I thought ‘there was no way I could not go back to West Brom’.

“I think it was obvious (leaving Celtic) to be honest. I did well in pre-season and then the first game came, and I didn’t play a minute.

“I thought the writing was on the wall. I don’t think much has to be said after that. At that point it was about finding my options and try and go and make big career. I feel like I have a chance to make a big career for myself, that’s what I want to do.”

It was not until into August, late in the window – after Albion had raised funds with the sales of Conor Townsend, Okay Yokuslu and Brandon Thomas-Asante, as well as the significant windfall for Dara O’Shea’s move form Burnley to Ipswich – that Albion’s £3million move become more of a possibility.

There was early window interest from Middlesbrough and Sheffield United – the reported late move from the latter was never a reality – but the firm attention on Johnston came from overseas.

Concrete interest from a big-hitting La Liga club was registered and there was also contact from the Bundesliga. Johnston has previous in playing abroad from a season in Portugal with Vitoria Guimaraes.

“Actually, I didn’t think it was going to be in the Championship at first, I thought it was going to be somewhere else,” Johnston adds. “When it came down to the teams in the Championship, and West Brom were an option, then I’d definitely be coming to West Brom.

“We were in contact, me and the gaffer, but at first he didn’t think it would be possible either, with the FFP rules, they couldn’t spend.

“I don’t know what happened, I think from Dara the club managed to get the money. It was quite late, genuinely, I tried to give West Brom every chance so it was possible to come back, that’s why it happened so late.”

So was Johnston’s relationship with Corberan the key reason the winger opted for the The Hawthorns over Turf Moor, where relegated Premier League Burnley had previously made the same offer?

He replies: “Yeah, ultimately he’s the one who is going to make me a better player and he just has so much knowledge and so much stuff you can learn from.

“Obviously the fans were big on me coming back and my friends as well down here. There were genuinely so many reasons. I’m not saying it was an easy decision, you talk to other people at other clubs, it’s just what happens in football. It was a difficult decision but it was the decision I made and I feel it was the right one.”

Johnston’s relationship with the adoring Albion faithful was, unsurprisingly, an immediate one after the trickster lit up his loan in an early run of six goals in seven games – many beauties from range.

It took no time for the ditty “He’s electric, we’ve signed him on loan from Celtic...” to Oasis’s She’s Electric to dominate matchdays.

Fitting timing, then, as his four-year deal was confirmed in the same week the Manchester band flogged tickets for their reunion phenomenon.

“I want tickets, I don’t know how I’m going to get them!” He smiles. “Everyone in the country wants one! I’ve had no luck immediately. I didn’t even bother with the queue, to be fair, but I’ll be trying to get one.”

One further piece of housekeeping to sort is Johnston’s squad number. He craved the number 23 that fared him so well in the second half of last season. You don’t need to be a basketball fan to know ‘MJ 23’ has a proper ring to it.

Unfortunately for Johnston that now belongs to the Baggies’ No.2 goalkeeper Joe Wildsmith. Instead the winger – who hopes to make his second debut for Albion at Portsmouth a week tomorrow – is set to choose between squad numbers 22 and 32.

The Baggies’ £3m man will look slightly different if he gets on the pitch in Hampshire next weekend – and not just due to the blonde highlights that Johnston claims attacker Swift took inspiration from this summer.

It is down to a black face mask he will wear for the next couple of weeks as recovery from a fractured eye socket steps up.

Johnston claims it is not too much of a concern: “It’s alright, it’s pretty annoying actually, it gets all sweaty, but it’s not that bad – I thought it would be worse! It doesn’t move about, hopefully it’s fine and doesn’t get in the way. It’ll hopefully be a couple of weeks.”

Blonde highlights and eye-mask or not, the Baggies faithful will have to tweak the “loan” lyric in his song, but Johnston hopes he will hear plenty more of Oasis this season.

“It was really nice,” he says. “I spoke about how it was tough to leave Celtic but it does make it easier when I feel the love from the fans, it was nice to go out against Swansea and hear my song.”