MASON, Ohio — Amid full-throated chants of “U-S-A!” around the grandstand at the Western & Southern Open on Thursday, Steve Johnson did what he does best: He ran around a backhand to slug a forehand return to beat ninth-ranked Jo-Wilfried Tsonga.
The victory secured Johnson the top spot in American men’s tennis, ending a three-year reign by John Isner. But after losing his quarterfinal match Friday against Grigor Dimitrov, Johnson will remain outside the top 20, making him the lowest-ranked man to ascend to the top rung of the American ladder.
Johnson, 26, won two individual and four team collegiate titles at Southern California, but he has not reached comparable heights on the world stage.