
That is when he will make his debut as coach of troubled Valencia, away to a Mallorca side who are always dangerous at home.
On Wednesday Koeman agreed to leave PSV Eindhoven and sign for Valencia until June 2010. A few hours later his new team was thrashed 5-1 at home by leaders Real Madrid, their fifth successive defeat in competitive games.
Koeman is due to be officially presented to the media by Valencia on Friday. He will then organise a quick training session, pick his first squad - and fly off with them to Palma.
Valencia have a massive injury list, though Carlos Marchena and David Villa could be fit by Sunday.
Valencia have slipped down to fifth in recent weeks. Mallorca are just two points behind them, in eighth place.
Later on Saturday, leaders Real are away to inconsistent Sevilla.
On Wednesday Sevilla lost 4-3 away to Atletico Madrid, a result which pulls them down to tenth.
Real are hoping that striker Gonzalo Higuain will be fit, though Robinho, Raul Gonzalez and Ruud Van Nistelrooy are doing so well that the Argentine has hardly been missed.
On Sunday, Barcelona should have few problems at home to lowly Real Betis, whether or not Thierry Henry gets over his Achilles tendon injury.
Betis are fourth from bottom after Wednesday's 0-3 meltdown at home to Osasuna.
A heavy defeat in the Camp Nou could be the beginning of the end for hapless coach Hector Cuper.
Barca were expected to move back into second place - two points behind Real - if they won away to Valladolid later on Thursday.
Sunday's other big game brings together two ambitious sides in fine form: Atletico Madrid and Villarreal.
Atleti will be sweating on the fitness of striker Diego Forlan, after he limped off at the start of Wednesday's win over Sevilla with muscle problems.
Villarreal, for their part, will stick with the attacking pair of Guille Franco and Giuseppe Rossi, both of whom scored in Wednesday's 3-0 win over bottom team Levante.
Levante will be trying to score their first win on Sunday, at home to Almeria, whilst fellow strugglers Valladolid go to Zaragoza and Getafe face Osasuna.
Sunday's other fixtures are as follows: Racing Santander-Espanyol, Murcia-Deportivo Coruna and Athletic Bilbao-Recreativo Huelva.
DPA