Some of the biggest names in men’s tennis, including two of the Big Three, could be on high alert as they kick off their 2020 Australian Open campaigns. Here are five men’s first-rounders to watch:
 Novak Djokovic (SRB) vs. Jan-Lennard Struff (GER)
No man in tennis history has won more Australian Opens than Djokovic—he’s a seven-time champion, and the defending titlist, and after leading Serbia to the ATP Cup title last week, he’s the favorite to win again in Melbourne.
But the Serb received one of the toughest first-round draws of any top player in Struff. The German is coming off the best year of his career, reaching the second week of a Grand Slam tournament for the first time, at Roland Garros,` and reaching a career-high ranking of No. 33. He was just two spots out of the seeds in Melbourne.
Djokovic has won both of the pair’s previous meetings in straight sets, including in the fourth round of the French Open last year, but the big-hitting Struff has been stepping up his game against the big names lately—five of the German’s seven career Top 10 wins have come in the last 11 months.
 Daniil Medvedev (RUS) vs. Frances Tiafoe (USA)
Tiafoe had a breakthrough Australian Open fortnight a year ago, reaching the first Grand Slam quarterfinal of his career, but his luck may have already run out this year. Medvedev is one of the hottest players in the sport over the last six months, getting to his first Grand Slam final at the US Open and coming into this tournament at a career-high ranking of No. 4.
If the No. 49-ranked Tiafoe loses this match, he could his see himself fall out of the Top 75.
The two have met once before at the tour level, in the third round of Washington last summer, and while the 6-2, 7-5 score may look routine—in the Russian's favor—it produced one of the best points of the year:
 Roger Federer (SUI) vs. Steve Johnson (USA)
Like Djokovic, Federer is an Australian Open legend. He’s won the title six times, including two of the last three years. His preparation was a little bit different this year, not playing any lead-up events over the last two weeks, but he had a good finish to 2019, winning Basel and reaching the semifinals of the ATP Finals. He also played a slew of exhibitions throughout the off-season.
He’s won both of his previous encounters with Johnson in straight sets, but neither match was easy, including a 7-6 (3), 7-6 (4) victory in their last meeting at Indian Wells in 2017, after which Federer praised the American’s serving.
“I just thought Stevie served very well,” Federer said. “He had chances in the first set to maybe get into better rallies. In the second set I think he was serving almost 90 percent at one point. That’s why I changed my position on the return. I thought he played a really good match.”
Johnson is currently ranked No. 81, but he’s been as high as No. 21 and has four career Top 10 wins.
 Fabio Fognini (ITA) vs. Reilly Opelka (USA)
There’s going to be a little bit of deja vu for Fognini and Opelka, who will play each other in the first round for the second straight Slam. It was Opelka who came out on top in the first round of the US Open last summer, dropping 26 aces en route to a 6-3, 6-4, 6-7 (6), 6-3 victory. Fognini got revenge in their only other meeting in the Davis Cup Finals a few months later, 6-4, 6-7 (4), 6-3.
Opelka has taken out Top 20 players in the first two rounds at three of the four Grand Slams last year: John Isner at the Australian Open, Stan Wawrinka at Wimbledon, and Fognini at the US Open.
 Roberto Bautista Agut (ESP) vs. Feliciano Lopez (ESP)
Bautista Agut didn’t just have a career year in 2019, reaching the quarterfinals of the Australian Open and semifinals of Wimbledon—as well as breaking the Top 10—but he’s gotten off to a fantastic start to 2020, winning all six of his matches at the ATP Cup last week, each in straight sets.
The No. 9-ranked Bautista Agut is an even 2-2 against Lopez, though, with all four matches being tight and including at least one 7-5 or 7-6 set. Lopez also has 38 career wins over Top 10 players.