Alistair Johnston believes the best is still to come for Celtic after the cinch Premiership champions opened up a 12-point gap with Rangers courtesy of a 3-2 win over their rivals last weekend.

Ange Postecoglou’s men weren’t at their best at Parkhead but they claimed the three points nonetheless as they took a significant step forward in retaining their title.

Johnston, who moved to Glasgow in January, gained plaudits for another successful showing in the game’s aftermath, following on from encouraging performances in his previous two derbies.

The 24-year-old, though, believes the victory served as proof that Celtic can continue to improve and reach a higher level.

“We kind of stay off social media so we don't get too much of it, but I've gotten a lot of nice text messages and people on the streets have said some really nice things about it, which is always a nice feeling,” Johnston said of his performance against Rangers.

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“At the same time I don't think we played particularly well. We strayed a little bit from our football so the exciting part is that we still won the match but we know that there's levels to that and we can play so much better than that.

“And that's what's exciting about this group. We're only scratching at the surface of our potential. I'm just really excited to be a part of it.

“I've already seen some growth within my game in handling those atmospheres and those moments. That was already my third match against Rangers and I've really enjoyed them.

“Those kinds of matches are why you signed for this club. You want to play in those big matches that mean that much to both yourself and your supporters. I've been quite happy with my performances in those matches and especially this past weekend.”

The Herald:

Onlookers to last week’s win over Rangers could be forgiven for not realising that Johnston has only been at the club for a matter of months, given the seamless nature of the defender’s transition to his new surroundings.

Despite arriving midway through the campaign, the full-back already has three outings against Rangers under his belt and he believes each encounter has thrown up its own unique challenges.

I think every single one has been competitive in its own right,” he said.

“I think they've tried a couple of different things now tactically and in this past match I think they definitely did some things that frustrated us, so that's kudos to them.

“But at the same time our biggest aim is to get out of there with three points and we've done that. That's what was most important for us.

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“A lot has been made about closing the gap but we're not focused on that. We're just focused on ourselves and we know that if we continue to get that one per cent better every day and continue to reach for the potential that we know this group has, then we feel really good that not only are we going to maintain a gap, or whatever you want to call it, that we can push on to new heights and new limits.

“That's the exciting part for this group, that we're not focused on what others are doing, we're just focused on ourselves. We know if we keep doing that, the sky's the limit for us.”