Charlton manager Karl Robinson admits he doesn't know whether Cristian Ceballos and Naby Sarr will be at the Valley this season.

Ceballos and Sarr failed to adjust to English football and spent last season on loan at Sint-Truiden and Red Star Paris, respectively.

But the pair have featured prominently in Robinson’s pre-season sides, and Ceballos did his first-team chances no harm after scoring in the Addicks’ 4-0 win over Greenwich Borough on Saturday evening.

Other goals from summer signings Mark Marshall, Billy Clarke and academy youngster Reeco Hackett-Fairchild made it two wins in a day for Charlton following their 3-0 triumph against Welling.

And Robinson says he has been impressed with Ceballos and Sarr since they returned to the club.

He said: “While they've been here, I've asked them to conduct themselves in the right way, to be respectful to the club and they've done all of that in a very professional manner.

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“You saw Naby at Greenwich Borough, would you have seen him come here two or three years ago running around and winning headers? Christian, too.

“They've really brought in to what we’re trying to do at the football club and they’ve put in a shift for us.”

Ceballos and Sarr signed in the summer of 2015 and appeared intermittently in Charlton’s Championship relegation campaign.

Ceballos was signed on a free transfer from Tottenham, while the Addicks paid Sporting Lisbon an undisclosed fee for Sarr.

When quizzed about their futures at the club, Robinson gave nothing away.

He added: “Will they still be here? Time will tell you that. Is there better out there? That’s the question.

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Naby Sarr and Karl Robinson | Picture: Benjamin Peters Photography

“So if we’re going to let these players go, we have to replace them with better.”

One player who won’t be at the Valley this season is Jorge Teixeira. The Portuguese defender signed a three-year deal with Sint-Truiden on Saturday.

He was one of Charlton’s highest earners, and his departure will free up room on the club’s wage bill.

Robinson spoke about how much he will miss the 30-year-old - and thanked him for his contribution.

He said: “I want to thank Tex - he’s been magnificent for me.

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“I’ll miss him around the training ground. But he's got a decent contract and he goes back home where his missus is from and it frees up things for us.

“It’s not just about the football sometimes, it’s also economics that surround different moves. We wish him all the luck in the world - he’s a great guy”