Melbourne Victory are sweating on the availability of first-choice central defensive pairing Adrian Leijer and newcomer Ubay Luzardo for Friday night's crunch clash with A-League leaders Central Coast Mariners.
Leijer has not trained this week with a groin injury.
Luzardo, a Spanish defender who has just joined the Victory on a loan deal, needs an international transfer clearance finalised in time to take his place at AAMI Park.
Magilton, still seeking his first win after five games in charge, would not reveal his preferred line-up.
But Thursday's training session indicated he wants the tall Luzardo to slot in alongside Leijer, allowing Mark Milligan to move into midfield.
That would cover for the absence of veteran midfielder Grant Brebner, who ruptured an ankle tendon in last round's scoreless draw with Melbourne Heart.
A scan on Wednesday gave Victory some hope the 34-year-old Scotsman could return later in the season.
If not, the two-time championship winner has probably played his last A-League match.
Magilton said Leijer's groin had troubled him throughout the season.
"He's done excellently to get himself through that and get himself to play," the coach said.
"So we'll see him tomorrow and then we'll make that assessment."
Magilton said the club were doing everything they could to speed Luzardo's clearance.
The match is desperately important for eighth-placed Melbourne, who sit three points outside the top six.
Magilton doubted the Mariners' first loss in 16 matches, to Brisbane Roar last round, would have dented the confidence he believes has been a key to their excellent season.
He said Victory were suffering from the reverse scenario, with missed opportunities to win matches causing players to doubt themselves.
"If there's a little bit of fear creeps in, things that you do naturally are taking a second longer," Magilton said.
He drew one positive from last round's draw - the Victory's first clean sheet in 14 matches.
The next step was for an attack boasting the talent of Archie Thompson, Harry Kewell and Carlos Hernandez to play to its potential.
"They've got to be able to step out across the white line and produce. There's no doubt on their day they can," Magilton said.
The Mariners have lost Pedj Bojic (knee) and Troy Hearfield (hamstring), but regained midfielder John Hutchinson from suspension.
Despite the vast gulf between the two sides on the ladder, Central Coast's Josh Rose acknowledged the Victory's potential.
"Melbourne Victory are always a dangerous team to play," Rose said.
"If you look at their forward line, they've got a lot of dangerous players."