Points won by each set: [ 39-39, 35-23… ]
Points won directly behind the serve:
20 % Del Potro – 13 of 65
19 % Nadal – 14 of 71
Nadal  had won their three previous meetings (all at Slams), but before the US Open ’18 semifinal he played three very tough matches that lasted 4:23, 3:19 & 4:49 (vs Khachanov, Basilashvili & Thiem respectively) while Del Potro  advanced to the semifinal not running as much as Nadal (3:00 Verdasco, 2:05 Coric, 3:31 Isner). I expected that Nadal’s only chance to beat DelPo again, it was to do it in straight sets. In the high-level opener, the Spaniard saved two set points at 4:5 to lead 6:5* (30/15), but once Del Potro won the tie-break 7/3, Nadal lost his enthusiasm. He was trying to play with a bandage around his knee, then without, then again with it; faster serves, shorter points – it didn’t look optimistic – he just wanted to finish the 2nd set before retirement. Del Potro advances to his second Grand Slam final after 9-year break… then he defeated in the semis Nadal too.