"Those top 2 are now losing ground to Novak Djokovic and Andy Murray" - When Andre Agassi predicted the end of Roger Federer-Rafael Nadal era in 2009

Andre Agassi once foresaw a changing of the guard in 2009, signaling the conclusion of Roger Federer and Rafael Nadal's era of dominance in the sport.

Federer and Nadal's sustained dominance into the last decade makes it difficult to envision a time when they were expected to relinquish their stranglehold on the highest echelon of the sport.

In 2009, Federer achieved a significant milestone by securing his first-ever French Open title to complete the coveted career Grand Slam. He then went on to defeat Andy Roddick in the Wimbledon Championships final, clinching his record-breaking 15th Grand Slam title and surpassing Pete Sampras' longstanding record.

That same year, Nadal claimed his maiden Australian Open title and his sixth Major title overall by triumphing over the Swiss legend in the final of the Melbourne Slam.

Despite the renowned duo's continued accomplishments, Andre Agassi predicted an imminent shift in the tennis hierarchy, with the likes of Novak Djokovic, Andy Murray and Juan Martin del Potro threatening the established order.

"Now we have possibly the changing of the guard. You have those top two who are now losing ground to the likes of (Novak) Djokovic and Murray and (Juan Martin) del Potro," he said (via The San Diego Union Tribune).

In 2009, Federer missed out on claiming his sixth consecutive US Open title, losing to a 21-year-old Del Potro in the final. Although Agassi admitted that the Swiss "still has the chance to do some more special things," he also argued that the then-28-year-old's opportunities for further success were diminishing with age.

Meanwhile, Nadal faced challenges due to recurring knee injuries following his shock fourth-round exit from the French Open that same year, prompting Agassi to predict that the Spaniard's injury struggles would persist for his entire career.

"If you’re struggling with your knee, it tends to be recurring and not to be easy to do, so I got to believe he’ll struggle with it probably for his career," Agassi said.

The American also expressed his belief that, in terms of talent, Andy Murray stood out among his peers as the player most likely to win multiple Grand Slam titles due to his versatile game.

"From a talent standpoint, Murray is a person who should win multiple Slams," Agassi said. "When I look at his game compared to the other players, he has what it takes to win and to win against anybody on any surface."

A brief look at Andre Agassi's head-to-head records against Roger Federer and Rafael Nadal

2009 French Open - Day Fifteen

Andre Agassi and Roger Federer locked horns in 11 tour-level encounters. While Agassi triumphed in their three initial encounters, Federer ultimately won their next eight meetings to establish his dominance in their rivalry.

The duo also faced off in four matches at Grand Slam tournaments, with the Swiss legend enjoying a 3-1 winning record. The American emerged victorious in their first-ever clash at a Major, winning 6-1, 6-2, 6-4 at the 2001 US Open.

The Swiss legend then defeated Agassi in the quarterfinals of the 2004 US Open and the 2005 Australian Open. Federer also claimed victory over the American in his last-ever appearance in a Major final, winning 6-3, 2-6, 7-6(1), 6-1 in the 2005 US Open final.

Rafael Nadal, meanwhile, enjoyed a flawless 2-0 record against Andre Agassi, defeating the American at the 2005 Canada Masters and 2006 Wimbledon Championships.