Erling Haaland handed Man Utd and Man City transfer warning by Mats Hummels

Mats Hummels has warned Erling Haaland that "the grass is not always greener" as reports continue to link the prolific striker with a move away from Borussia Dortmund.

Haaland only signed for the Bundesliga giants at the start of 2020, but with a staggering record of 68 goals from 67 games, he is one of the most sought after players on the planet.

All of Europe's big hitters have been linked with the Norwegian, including Manchester rivals United and City.

The Red Devils missed out on his signing when he made the switch to Dortmund, despite manager Ole Gunnar Solskjaer's existing relationship with the player.

Erling Haaland has 68 goals in just 67 games for Borussia Dortmund ( Image:

REUTERS)

City are also set to be in the market for a striker at the end of the season, after missing out on top target Harry Kane this time around.

According to the Times, City bosses are ready to shelve plans of signing the England captain, with Haaland now their priority to replace Sergio Aguero.

However, his Dortmund team-mate Hummels has told him to think very carefully about his next move. The centre-back left Dortmund in 2016 for Bayern Munich, but returned three years later, with the experience that every team doesn't offer what he currently has.

"I would fully understand him wanting to stay!" Haaland told Sport Bild. "Because things are really great in Dortmund, because he knows what he has here. I have far from given up hope that he will stay for a long time.

"The grass is not always greener on the other side. You really have to be aware of that in football.

"It's worth a lot if you have a good environment, feel comfortable with the guys and can also be really successful.

"You have to value that, that's not a given at every club. So we have a lot to offer to Erling."

At the start of next summer's window, Haaland's release clause, which is set at £68million, is set to kick-off a continent wide clamour for his signature.

Mats Hummels has warned his Dortmund team-mate about leaving the club

Reports in Spain had suggested that the forward's agent, Mino Raiola has already secured an agreement with Real Madrid, something which Dortmund chief Hans-Joachime Watze strongly denied.

"It's all b******s," Watzke told Sport1 last month. "Some experts say, 'They're in the stock market, they're going to have to sell Haaland next summer.'

"The decision as to whether or not to sell someone at our club is taken exclusively by the board.

"It has not yet been decided if he will leave next summer. We'll see."

Watzke has admitted it will be tricky to keep hold of their most prized asset, months after finally allowing Jadon Sancho to leave in a deal worth £73m.

He added: "Of course it will be difficult. I am not saying, however, that it is completely out of the question.

"We'll do everything we can to keep our top players loyal to us in the future."