Celtic manager Martin O’Neill has confirmed that full-back Alistair Johnston will be sidelined until mid-October after a serious injury that also cost him a move to Everton. The Canadian, who played the opening game of the season, suffered a setback during a match against Kilmarnock and was later diagnosed with a condition that required surgery.

O’Neill said the injury “probably stopped him from getting to the Premier League” and that Johnston’s absence could force the club into the transfer market. “We’ll need to have a look at it,” he told reporters. “If we are looking at European football, I just think we could do with a couple of extra players in.”

The club is already pursuing midfield options and is expected to sign left-back Landon Emenalo. O’Neill also praised Colby Donovan, who joined the squad last Wednesday and has impressed in training, and mentioned Tony Ralston as part of the potential reinforcement list.

Celtic’s next challenge is a Champions League second-leg tie against LASK. O’Neill expressed confidence that the team will “blast past LASK tonight and reach the Champions League.” He reminded the squad of the 2003 UEFA Cup tie against Stuttgart, where the Hoops had a strong start but ultimately lost momentum. “We have to try not to sit in too much, try to get forward and just go for it,” he said.

In other training news, centre-back Auston Trusty missed yesterday’s session in Glasgow due to an upset stomach, but O’Neill expects him to be fit for the match in Austria. “He’s travelled. He had a bit of an upset stomach this morning, so he didn’t train,” the manager said.

LASK’s boss Dietmar Kuhbauer warned that the team would “throw the kitchen sink” at Celtic, but O’Neill dismissed the idea of panic. “They are a good side, physically strong with a bit of pace up front,” he noted. “It’s important for us and it’s grounds for optimism.”

With Johnston out until October, O’Neill is keen to secure a replacement quickly. He added that the club’s European ambitions will keep them in the Champions League until January, giving them a window to strengthen the squad.

The match against LASK remains a priority as Celtic aim to secure a place in the group stage, while the club’s transfer activity will be shaped by Johnston’s long-term absence.