Owen was missing from the side which secured a creditable 1-1 draw at Manchester United in Sunday's Premier League opener after a summer disrupted by a bout of mumps and a calf problem.

With Viduka also sidelined as he recovers from an Achilles injury, Keegan was short of options at Old Trafford and therefore delighted by Obafemi Martins' return to action.

Martins headed the Magpies into a shock lead at United, and he looks likely to lead the line once again when Bolton visit St James' Park on Saturday with Owen and Viduka set to sit out once again.

Keegan admits he could probably send the former Liverpool and Real Madrid frontman out against Gary Megson's side if he needed to, but is acutely aware of the possible consequences.

He said: "Michael probably won't be (fit), and Mark Viduka certainly won't be.

"I probably could rush Michael back and then knock him back five or six weeks.

"We are probably strong enough to do without the two of them - but when they come back, it will give us a massive boost."

That is perhaps a measure of the growing optimism in the wake of Sunday's performance, in which new signings Jonas Gutierrez, Fabricio Coloccini and Danny Guthrie made excellent league debuts.

Owen could make the Carling Cup trip to Coventry next Tuesday evening, but is more likely to return for another tough Premier League assignment at Arsenal the following Saturday.

Viduka has returned to training, but is still some way off figuring, while defender Steven Taylor is expected to shake off the ankle injury he picked up at the weekend after withdrawing from the England Under-21s squad for last night's friendly victory over Slovenia in Hull.

Meanwhile, reports in Belgium have claimed the Magpies are ready to step up their interest in international full-back Sebastian Pocognoli on his return from the Olympic Games in Beijing.

The left-back, who plays his football in Holland with AZ Alkmaar, is heading for home after his side were beaten in the semi-finals by Nigeria.

Keegan has been targeting a left-sided full-back for much of the summer with Jose Enrique the club's only senior specialist.

Midfielder Charles N'Zogbia was once again asked to play there against United, but it is no secret that he does not particularly enjoy the role.

Newcastle have previously been linked with Blackburn's Stephen Warnock and Liverpool's Emiliano Insua, but have as yet received little encouragement.