Eastbourne Eagles are poised to bring Edward Kennett back to Arlington after suffering another injury blow.
Stefan Andersson is expected to miss Saturday's home clash with title favourites Swindon due to ongoing health problems.
Kennett, currently on loan from Eastbourne to Poole, is on standby to act as guest replacement.
Andersson fell after less than 30 yards of his Arlington comeback in last Saturday's win over Wolves.
He went out again for heat four but was off the pace and retired.
Medical staff checked him over seconds before he was due to compete in heat six and declared him unfit to race.
Andersson has been struggling since taking a blow to the head in a recent crash in Poland.
Now Eagles team manager Trevor Geer wants him to be 100 per cent before attempting a comeback.
Geer said: "He was okay leading up to the meeting on Saturday. Then about ten minutes before the meeting he was struggling.
"He fell off on his own in the first race and in the second he had to pull out. He just couldn't see and wasn't with it at all.
"I don't want him coming back too early."
Andersson has not hit form this season after returning for a third spell with Eastbourne.
But the fact he has not yet ridden enough meetings to qualify for a new average works in Eagles' favour.
Geer waited until new averages arrived on Monday afternoon before making his move.
Eagles were allowed to hire a rider with an average up to the Swede's pre-season figure of 5.76 and Kennett, in superb early-season form, should represent great value.
As well as taking his own four heats, he is also eligible for one of four replacement rides for injured Davey Watt.
Swindon, who face Coventry tomorrow have doubts over Polish star Seb Ulamek, who broke his thumb in Poland on Sunday.
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