Celtic's new permanent manager, Martin O'Neill, has described last season as a 'wake-up call' for the Scottish champions, but the club's slow pace of transfer activity has raised concerns that they may not be acting quickly enough to address their weaknesses.
O'Neill, who was appointed on a one-year contract on 11 June, has admitted that he is expecting a tough season ahead, with Rangers and Hearts expected to be strong competitors.
Celtic secured their 14th Premiership crown in 15 years in remarkable fashion, winning their final seven matches to snatch the title from under the noses of Hearts. However, the club's playing squad is in urgent need of reinforcements and more quality, yet they are currently one of only two Premiership clubs yet to make a single signing.
Hearts, on the other hand, have already signed seven players in their squad rebuild, while Rangers have landed Tynecastle striker Lawrence Shankland and fellow Scotland international Ross McCrorie from Bristol City.
O'Neill has had little time to digest last season's success, which came after a dramatic final-day win over Hearts, and has thrown himself into planning for the new campaign. The potential for regrets and the importance of the Champions League also played a part in his decision to take the post full-time.