Jürgen Klopp has asked to leave Borussia Dortmund in the summer, according to a top sports betting expert and, in what seems to be a confirmation of this, the club called a press conference at 1.30pm CET on Wednesday. Klopp had been heavily linked with Arsenal and Liverpool in the past, although both clubs are currently thought to be happy with their managers, but now, considering Manuel Pellegrini’s fate at Manchester City looks far more uncertain, with the club now at risk of missing out on the Champions League, the citizens are on alert. A top football tipster suggested that City had been linked with a move for Rafa Benitez in recent weeks, although Bayern Munich boss Pep Guardiola is thought to be a long-term target.The 47-year-old German manager has a contract with Dortmund until 2018 but, he has asked the Dortmund CEO Hans-Joachim Watzke to allow him to leave at the end of the season. It has been a difficult season at Dortmund with the team in the bottom half of the table for long periods of the campaign and they were eliminated, and very much outplayed, by Juventus in the Last 16 of the Champions League. Klopp had joined Borussia from Mainz seven years ago and has managed to win the Bundesliga title twice, the German Cup once and reach the Champions League final against Bayern Munich in 2013, a game they lost 2-1 but many a football tipster thought they had deserved to win. The best football predictions would suggest that Thomas Tuchel, who replaced Klopp at Mainz, is the favourite to take over should there be a change at Dortmund in the summer especially since Tuchel, who was offered the job of managing Hamburg this week, seems to have turned it down. In other news, Chelsea are closing in on the signing of Brazilian youngster Nathan, according to our top football tipster. There have been reports that suggest that Nathan has arrived in London for a medical after being granted permission by his present club, AtleticoParamaense, to discuss personal terms. The youngster rose to prominence with his performances in the World U-17 Championships two years ago and can play in any of the three attacking positions, behind the striker and on both flanks. The premier League champions City, had been trying to tie up a deal after first spotting the player at the World Under 17 Championships, but nothing happened and now the 19-year-old is considered as one of several exciting young talents in Brazil and he is now expected at Chelsea on Wednesday to discuss a £4.5m transfer move.