Mixed doubles is often eschewed to the outer courts during Grand Slam events, but the popular team of Martina Hingis and Leander Paes have been giving it a much-needed boost with their dominance in 2015.

The pair won the Australian Open and Wimbledon mixed doubles titles this year without the loss of a set and have now added the US Open to their collection. Down 1-4 in the deciding super tiebreak of their final against Bethanie Mattek-Sands and Sam Querrey, they rallied with a series of winners to clinch the title, 6-4, 3-6, [10-7].

But just as importantly, the win established them the most dominant mixed doubles team of the last 45 years. Paes and Hingis are only the second mixed doubles team in the Open era (and the first since 1969) to win three Grand Slams in the same year.

“The understanding we have for the game and each other is amazing. Even if one thing doesn’t work, we come up with a plan B or C like we did today,” said Hingis. “I just feel like we’re almost invincible going on court.”

The win also gave Paes his ninth mixed doubles title, more than any other man in the Open era. Only Martina Navratilova has more than him among players in the Open era, with 10 titles. But Paes believes there’s nothing specific about his game that translates so well to mixed doubles. Instead, it’s his personality that has led to incredible Grand Slam success

“I don’t believe that I have the technique or caliber of talent that [Hingis] has. What I do have is the guts. I will go for it,” said Paes. “In any partnership, there's got to be one person who brings the energy to the team, who takes all the pressure on their shoulder and drives the team forward. I know if I can keep Martina happy and relaxed, I don’t even have to worry about the tennis.”

Paes and Hingis have played mixed doubles together for years in World Team Tennis as part of the Washington Kastles franchise, helping that team to five consecutive championship titles, but hadn’t played in a Grand Slam until this year. Their time on the court has also turned into a friendship far closer than most mixed doubles teams in the draw this year. Paes and Hingis even practiced together regularly before their matches.

“When we go out there and play for an hour, we are generally getting in a block of four or five hours of quality in that one hour,” said Paes.  “I have a reputation of not wanting to practice so much, but it's because the quality of practice is so good I don't have to do the same number of hours as others.”

The pair have already confirmed they will play together in 2016 and if they can maintain their current form, they will likely be lifting up many more trophies in the future.

“We don't have the biggest serves or returns, but we are stable and we do the basics as well as anybody,” said Hingis. “Our solid base is just so high that our opponents have to overperform to win. We have a little bit of this aura and they have to come up with their best game to beat us.”