A clearly hurting Rafael Nadal lost his second-round match at the Australian Open to Mackenzie McDonald 6-4, 6-4, 7-5 on Wednesday, abruptly ending his title defense and bid for a record-extending 23rd Grand Slam trophy. It was not immediately clear what was bothering the 35-year-old Spaniard, but he pulled up awkwardly at the end of a point late in the second set against the 65th-ranked McDonald. The No. 1-seeded Nadal was visited by a trainer on the sideline, then left the court for a medical timeout. Up in the stands, his wife wiped away tears. Nadal returned to play, but was physically compromised and not his usual indefatigable self. “He's an incredible champion. He’s never going to give up, regardless of the situation, so even closing it out against a top guy like that is always tough,” said McDonald, a 27-year-old American who won NCAA championships in singles and doubles for UCLA in 2016. “I kept focusing on myself in the end and got through.” This is Nadal’s earliest exit at any Grand Slam tournament since bowing out in the first round in Melbourne in 2016 against No. 45 Fernando Verdasco. That also made Verdasco the lowest-ranked player to defeat Nadal in Australia — until, of course, McDonald on Wednesday. McDonald has never been past the fourth round at a major tournament. In his lone previous matchup against Nadal, at the 2020 French Open, McDonald won a total of just four games in a lopsided loss. A year ago, Nadal won the Australian Open for the second time to earn his 21st major championship, then raised his total to 22 — the most for a man — at Roland Garros. He is currently ranked No. 2 but was the top seed at Melbourne Park because No. 1 Carlos Alcaraz is sitting out the Australian Open with a bad leg. Nadal has dealt with a series of health issues recently. He needed pain-killing injections for his left foot on the way to winning the French Open last June, pulled out of Wimbledon last July before the semifinals because of a torn abdominal muscle and also dealt with a problem with rib cartilage in 2022. Nadal’s exit drains the tournament of yet more star power. In addition to his absence and Alcaraz’s, 2022 Wimbledon runner-up Nick Kyrgios pulled out because his left knee needs arthroscopic surgery, four-time Grand Slam champion Naomi Osaka is off the tour while she is pregnant, two-time major champ Simona Halep is serving a provisional doping ban and Venus Williams is hurt. That is all on top of this: The 2023 edition of the Australian Open is the first Grand Slam tournament since Serena Williams and Roger Federer announced their retirements. Nadal arrived in Melbourne with an 0-2 record this season, making him 1-6 dating to September, when he lost to Frances Tiafoe in the fourth round of the US Open. Even during a first-round victory Monday, a four-setter against a cramping Jack Draper, Nadal never quite seemed to be at his chase-every-ball, put-every-high-spin-shot-on-target best. He looked, somehow, his age. The same was the case from the outset against McDonald. “I’m really happy with how I started that match. I thought I was playing really well, serving great, returning well, too,” McDonald said. “So I was really taking it to him.”