SHOWCASE-Tennis-Johnson seeks paternal inspiration against high-flying Thiem

PARIS, June 2 (Reuters) - Steve Johnson will hope to again draw inspiration from the memory of his late father on Friday when he faces his biggest French Open challenge yet - taking on the only man to beat Rafael Nadal on clay this season. The American will battle for a place in the fourth round against Austrian sixth seed Dominic Thiem, whose stellar run on the red dirt was capped by a straight sets win earlier this month in Rome over the world's greatest player on the surface. Johnson, seeded 25th, whose father died aged 58 less than three weeks ago, broke down in tears after his second-round win in four sets over Croatian Borna Coric on Wednesday. "I know he was looking down on me on that last point and gave me the strength to finish it off," he said courtside following the match. Johnson will need to be on top form against Thiem, a semi-finalist in 2016 whose untroubled progress at Roland Garros this time around has strengthened his standing as one of the dark horses for the title. (Reporting by John Stonestreet; Editing by Ken Ferris)