The Old Guard has returned to the top of men’s tennis in 2017. Roger Federer and Rafael Nadal, both counted out at the end of last year as old, battered players on the decline, have dominated the first half of the tennis season, blowing away their competition in nearly every tournament.

After a few warm-up tournaments in Asia and Oceania, the tennis season kicked into high-gear in mid-January when the sport’s biggest names arrived in Melbourne for the 2017 Australian Open. Andy Murray, the new World Number One, entered a Grand Slam tournament as the top seed for the first time in his career. He, along with second-seeded Novak Djokovic had dominated the sport for the year, battling for the tour’s biggest titles. Nadal and Federer, who had both struggled with injury for much of the 2016 season, entered the tournament as long shots. The two legends are accustomed to having a “1” or a “2” placed next to their names, but were pushed down in the rankings; Nadal entered the tournament as the ninth seed, while Federer entered as the seventeenth.

Despite their respective rankings, the two veterans tore their way through the draw, eliminating the younger competition. Federer defeated the likes of Tomas Berdych, Kei Nishikori, and Stan Wawrinka en route to the championship match. Nadal, meanwhile, battled past Gael Monfils, Milos Raonic and Grigor Dimitrov to reach the final. Many analysts lauded the final as the most anticipated match in decades; the two rivals had not faced off in a Major final since 2011, and given their age (Federer, 35, and Nadal, then 30), were likely to never square off in a Major final again. Nadal had history at his back. He had defeated Federer in the 2009 Australian Open final in an epic five-setter, and hadn’t yet lost to Federer in a Major outside of Wimbledon. The 2017 final was yet another epic, with the two legends battling back-and-forth for a return to glory. After being down two-sets-to-one, Nadal battled back, took the fourth set, and went up a break in the fifth. Despite the Spaniard’s best efforts, the determined Federer would not let the title slip from his grasp, and ran away with the fifth set 6-3.

Again atop the tennis world, Federer continued to dominate the first three months of the season. In the first Masters 1000 tournament of the year at Indian Wells, Federer defeated Nadal in straight sets en route to the title, defeating compatriot Stan Wawrinka in the final. At the Miami Masters, considered by some analysts to be the unofficial “fifth slam,” Federer and Nadal again squared off in the final, with Federer triumphant. The Swiss legend had taken each of the three biggest tournaments of the first quarter of the year, with Nadal running a close second to Federer’s dominance.

In May, Federer announced that he would not participate in the spring clay-court swing, including three Masters 1000 tournaments and the French Open. Nadal, who relishes the red dirt, commenced his dominance of the second quarter of the season. He dropped just one set on his way to the title at the Monte-Carlo Masters, becoming the first man in the Open Era to win ten titles at a single tournament. Nadal again dominated the Barcelona Open, winning the tournament without dropping a set. The King of Clay notched a third straight title by winning the Madrid Masters and defeating rival Novak Djokovic on the way in straight sets. Though Nadal’s perfect clay season was interrupted by a loss at the Rome Masters, he entered the French Open as the clear favorite.

Nadal played perfect tennis nearly the entire tournament, dominating his opponent in every round. By defeating Stan Wawrinka in the final 6-2, 6-3, 6-1, Nadal claimed the French Open without losing a single set and dropping just 35 games over the course of the entire tournament. By winning at Roland Garros, Nadal became the first man to ever win a single Grand Slam tournament ten times.

The resurgence of Federer and Nadal, along with the emergence of Swiss veteran Stan Wawrinka as a powerful force on the tour, marks a significant shift in the age barrier of the men’s game. From the Golden Age of the 1970s and 1980s to the whirlwind 1990s owned by the likes of Agassi and Sampras, tennis was always seen as a teenager’s sport. Most stars made a name for themselves in their late teens and had racked up most of their achievements by their early to mid-twenties. Age thirty was seen as the the towering barrier few could surmount in striving for tennis greatness, the unofficial retirement age of tennis players. Regardless, these past five years of tennis have seen the dominance of veteran players.

Most “young” and up-and-coming players are now in their mid-twenties, such as Milos Raonic and Grigor Dimitrov (both 26). Each of the dominant players of day have now passed thirty; Federer is 35, Nadal 31, Djokovic and Murray both 30, and Wawrinka 32. Wawrinka’s rise has particularly mirrored the older shift in the men’s game. Wawrinka spent much of his career swimming through the top-30, occasionally breaking into the top-10. It wasn’t until age 28, when he notched his first Grand Slam title at the 2014 Australian Open, that his consistency peaked. Since then, Wawrinka has threatened the dominance of the Big Four by playing the best tennis of his life, post-30. He beat Djokovic to win the 2015 French Open at age 30 and again beat the Serb to win the 2016 US Open at age 31. At age 32, he reached the 2017 French Open final to solidify a showdown of veterans as he stood against the 31-year-old Nadal.

Some have attributed the older shift of the game of tennis to the growing need for athleticism and strength in a game evolving towards greater power and spin. Additionally, the mental toughness possessed by veterans has become increasingly important in winning seven grueling best-of-five set matches. The evolution of tennis towards a 30-year-old’s sport has elongated the era of dominance of the Big Four, potentially a boon for a sport blessed with four superstars in Federer, Nadal, Djokovic and Murray. Though younger players such as Marin Cilic have been able to make smaller breakthroughs, no youngster has interrupted the dominance of the men’s game by stronger, tougher, older veterans.