If it's spring, clay is the only game in play.
And suddenly, the third ATP World Tour Masters 1000 event of season -- Monte Carlo -- is already upon us. Main draw action began Sunday, with clay Masters in Madrid and Rome to follow May 7 and May 14.
While Roger Federer (understandably at 35) is sitting this one out after winning the season's first three biggest tournaments, this is our first look at the No. 1- and No. 2-ranked players in ATP action since Indian Wells. Both Andy Murray and Novak Djokovic subsequently skipped Miami with elbow injuries but are locked in at the top and bottom spots of the loaded Monte Carlo draw.
Seven of the ATP's top 10, 14 of the top 20 and three former champions are in the field.
Here's what we're watching for at this week's only ATP event:
Monte Carlo Rolex Masters, Monte Carlo Country Club, outdoor clay
1. Andy Murray: The 29-year-old Scot has been sidelined for over a month nursing that elbow, but he showed up a week early in Monte Carlo to ease the transition to clay. Not that hard courts were cruel in the season's first two months. Murray is 12-3 with a finals appearance in Doha (losing to Djokovic) and a win in Dubai.
Murray lost in the fourth round of the Australian Open to Mischa Zverev. Murray has never won here but reached the semifinals a year ago (losing to Rafael Nadal there for the third time), as well as in 2009 and 2011. He's got an easier draw with, theoretically, Marin Cilic in the quarters and Stan Wawrinka in the semifinals.
2. Novak Djokovic: This is a home game for Nole, who could walk to the tournament from his primary residence. He surfaced earlier than Murray, winning a Davis Cup singles match last week against Spain, which helped lift Serbia into the semifinals. Djokovic, 29, came flying out of the 2017 box, winning at Doha, but he was stunned in the second round of the Australian Open by journeyman Denis Istomin.
In results that could be significant going forward, Djokovic lost his third matches in both Acapulco and Indian Wells to the same player -- rising Australian Nick Kyrgios, each in straight sets. Djokovic won Monte Carlo in 2013 and 2015 and has been to two other finals. Djokovic and Nadal are first and second all time with 30 and 28 Masters titles, respectively.
3. Stan Wawrinka: No titles this year for the three-time major champion, but that's because he's already gone down to Federer twice. Wawrinka, 32, fell to his Swiss Davis Cup partner in the semifinals of the Australian Open -- in five sets -- and again in the Indian Wells final. He exited in Miami in the fourth round, courtesy of German teenager Alexander Zverev. Don't forget: Wawrinka's only Masters win came here in 2014.
4. Rafael Nadal: Fun fact: Seventeen of Rafa's career 69 titles have come in April, his best month, followed by May (12), June (11) and July (7). There was a substantial flow of social media shots showing Rafa practicing on the red clay of his tennis academy in Mallorca, Spain. After a remarkable start to 2017, he can't wait to get started on the dirt. Like Wawrinka, Nadal couldn't get over the Federer hump, losing to him in the finals at Melbourne and Miami (not to mention the fourth round at Indian Wells). But with Federer sitting most of the clay season out, this should be a fun run for Nadal, who turns 31 at this year's French Open.
There's some added incentive, too. He's a nine-time Monte Carlo champion, a record. Don't think for a moment he's not hungry for No. 10. He could see Zverev in the round of 16, Grigor Dimitrov in the quarters -- and Djokovic in the semifinals. This would be his 50th clay-court title, breaking a tie with Guillermo Vilas as the Open era leader.
5. Marin Cilic: It's been a rough start for the 2014 US Open champion. Cilic is 5-7 and has been one-and-done in four tournaments this year. Most recently, he fell to 19-year-old American Taylor Fritz in Indian Wells and Jeremy Chardy in Miami. Cilic has never advanced past the quarterfinals in the Monte Carlo-Madrid-Rome trilogy in 24 total tries.
6. Dominic Thiem: After vowing not to overplay -- following an exhausting 2016 -- the 23-year-old Austrian is already appearing in his 10th event of 2017. He's a sturdy 17-8 but lost his first match in Miami to Borna Coric, 20. However, Thiem's only title this year, in Rio de Janeiro, was also on outdoor clay.
7. Jo-Wilfried Tsonga: Lost in Federer's resurgence is the success of another old campaigner, the 31-year-old Frenchman. Tsonga is 17-4 and won titles in Rotterdam and Marseille. After losing to Fabio Fognini in the first round of Indian Wells, Tsonga hurried home to Switzerland to join his girlfriend in welcoming the March 18 birth of his son, Shugar. Tsonga has reached the semifinals in Monte Carlo twice, most recently last year.
8. Grigor Dimitrov: Like Tsonga, the 25-year-old Bulgarian is 17-4 with two titles -- Brisbane and Sofia, Bulgaria. More impressive was his five-set battle with Nadal in the semifinals of the Australian Open. That loss went a long way toward suggesting Dimitrov is taking the game more seriously now. Dimitrov, who went 1-2 in Indian Wells and Miami, lost in last year's second round at Monte Carlo but is a two-time quarterfinalist.
Of note: The following marquee players are not playing: Federer, Milos Raonic, Kei Nishikori, Gael Monfils and Richard Gasquet. Most troubling is Raonic, whose health is becoming a concern. The 26-year-old Canadian says he hasn't gotten through a tournament at 100 percent since last year's Wimbledon, where he reached his first major final. A right hamstring injury forced him to grant a third-round walkover to James Donaldson in Miami and earlier he was forced to skip the Delray Beach final opposite Jack Sock.
Also taking the week off: The U.S. Davis Cup team -- Sock, John Isner, Sam Querrey and Steve Johnson -- which is coming off a loss in Australia and a quick-turnaround in Houston. While Johnson won the title, Sock (who, with David Goffin, has an ATP-high 20 wins) made the semifinals. One American who will play Monte Carlo for the first time is Ryan Harrison. He's a newlywed, having married Lauren McHale -- sister of WTA pro Christina McHale -- on March 31 in Austin, Texas.
Four top-10 players -- Djokovic, Wawrinka, Cilic and Thiem -- are also playing doubles.