Tsitsipas 1st Greek in 83 years to reach last 16 at French

     Stefanos Tsitsipas overcame a ''psychological'' challenge and lethargic legs to become the first Greek player - man or woman - to reach the fourth round of the French Open in more than 80 years.  The sixth-seeded Tsitsipas saved a set point in the fourth-set tiebreaker of a 7-5, 6-3, 6-7 (5), 7-6 (6) win over 60th-ranked Filip Krajinovic that lasted two days.  The last Greek player to go this far at Roland Garros was Lazaros Stalios way back in 1936.  ''It's very tricky when you come back after a day. It's something very unusual, very psychological. You tend to think about the match all the time. It's not easy with the nerves,'' the 20-year-old Tsitsipas said. ''But I got the job done.''  Up next for Tsitsipas is either 2015 champion Stanislas Wawrinka or Grigor Dimitrov. After that, Tsitsipas could meet Roger Federer.