Giakoumakis is set to end his association with Celtic to make the switch to the MLS, where he will look to get back into the groove of regular starts.
The Greece international fell out of favour at Celtic, but there was no shortage of sides willing to sign him and a scramble for his signature resulted in Atlanta United winning the race.
Celtic will pick up £3.3m from selling Giakoumakis to Atlanta United, but they have also successfully included a host of add-ons in the agreement.
There are a variety of add-ons which could see Celtic net extra cash, from Giakoumakis scoring 15 or more goals to him being named in the MLS Best XI.
The Scottish giants also have a sell-on clause in the agreement.
However, it will only apply if Giakoumakis moves to a non-MLS club and not within the MLS itself.
Time will tell whether Celtic regret their decision to sell Giakoumakis and not hand him a leading role at the club.