The Brazilian picked up the injury during their third-round visit to rivals Sunderland in the FA Cup.

Harvey Barnes (26), Jacob Murphy (28), Elliot Anderson (21), Matt Targett (28), Joe Willock (24), Nick Pope (31) and Callum Wilson (31) are among the long-term absentees at Newcastle.

"It isn't good, it is an injury that will see him miss a minimum of six weeks, it is a real blow for us," Howe told reporters ahead of Saturday's Premier League clash against Manchester City.

"He is such an important player. He has a problem with his tendon in his quad. He is very disappointed, he wants to play and do well - we have had to try and pick him up. He is our midfield driving force, it is a big blow."

Howe said Newcastle had not already bolstered their squad in January's transfer window due to Financial Fair Play rules.

Newcastle, who in October 2021 were acquired by a group led by Saudi Arabia's Public Investment Fund, reported a loss of 73.4 million pounds ($93.59 million) in their latest financial results.

"We're really stretched in attacking and midfield areas and that's inhibited our players from resting and bringing new players on to help with rotation," Howe said.

"In an ideal world, given the freedom to act, we'd have brought players in already, but we're not in that situation because financial fair play is a problem for us. So, we're having to navigate around that."

Howe, who will manage his 650th game on the weekend, said his side will put up a strong fight against champions City. City are third in the table, while Newcastle sit ninth after exiting the Champions League and League Cup.

"They are the team to beat, their record in recent seasons has been incredible. They have the best manager in the world, their style of play is difficult to combat, but I believe we can really compete in this game," he said.

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