Mitrovic is still to respond to the Magpies’ latest attempts to wrap up his transfer, with sources in Belgium claiming he is continuing to hold out for a possible move to Porto.
The Portuguese side have confirmed their interest in the Serbian striker, but are still to agree an acceptable fee with Anderlecht or finalise personal terms.
Newcastle officials remain reasonably confident that their bid will trump anything on offer from Porto officials, but the longer the impasse continues, the greater the temptation to walk away and look elsewhere.
As things stand, Newcastle’s recruitment team are likely to wait until the end of the week before pressing Mitrovic and his agent, Pini Zahavi, for a final decision.
They continue to monitor alternative attacking targets, most notably Wolfsburg forward Bas Dost, but McClaren remains hopeful that a deal for Mitrovic can be concluded.
The Magpies are confident of making their second signing of the summer following the arrival of Georginio Wijnaldum from PSV
Newcastle manager Steve McClaren says the club are “very close” to signing Anderlecht striker Aleksandar Mitrovic.
The player’s agent Pini Zahavi has already revealed he expects the striker, who scored 20 goals in 37 Belgian Pro League games, to move to St James’ Park this summer.
McClaren’s side continued their pre-season preparations with a 1-0 win over Sacramento Republic and, speaking after the game, the 54-year-old revealed he is confident a deal is imminent.
“We are very close to something,” he told reporters after the 1-0 win over Sacramento Republic when asked about Mitrovic.
“There is a lot of speculation and pre-empting of decisions. But certainly from the feedback back home they are working very hard to bring one or two players back in.”
Newcastle, who have already signed Georginio Wijnaldum from PSV, take on MLS side Portland Timbers next but McClaren says the Mitrovic deal will not be done before the game.
“No I don’t think so,” he added. “We have what we have, it’s a good squad. We now go to Portland and it will be a totally different game.
“I am so pleased with the games we have had so far in terms of how they boys have worked.
“They are getting minutes in and working hard. Their attitude is very good.”