After securing their 44th Scottish League Championship with a 4-1 home win against Inverness in April and with the Scottish Cup final coming up this month, the summer transfer window could be a busy period for Celtic this year.
Manager Neil Lennon has some thinking to do as fierce rivals Rangers enter the Scottish Second Division next season—Rangers were champions of the third tier after their liquidation last summer. With this in mind, he will have to look for some good long-term signings as it is likely Rangers will enjoy a second successive promotion and re-enter the Scottish Premier League next year; as such, both Lennon and Celtic will be mindful of continuing their recent dominance of the Old Firm rivalry.
Celtic may also have to deal with the loss of some of their star players this summer, such as forward Gary Hooper, midfielder Victor Wanyama and goalkeeper Fraser Forster.
This considered, Celtic will have to invest their money wisely this summer to continue their dominance of Scottish football and make an impression in Europe following this year's last-16 exit to Juventus.
So which players would fit the bill without breaking the bank? Here are the top five candidates.