Bjorn Borg was born in Stockholm, Sweden, on 6 June 1956, as the only child of Rune and Margaretha Borg. He grew up in nearby Sodertalje. As a child, Borg became fascinated with a golden tennis racket that his father won at a table-tennis tournament. His father gave him the racket, beginning his tennis career.

With 11 Grand Slam titles, Borg ranks sixth in the list of male tennis players who have won the most Grand Slam singles titles behind Roger Federer (20), Rafael Nadal (16), Pete Sampras (14), Roy Emerson (12), and Novak Djokovic (12). The French Open--Wimbledon double he achieved three times consecutively was called by Wimbledon officials "the most difficult double in tennis" and "a feat considered impossible among today's players." Only Nadal (in 2008 and 2010) and Federer (in 2009) have managed to achieve this double since, and Andre Agassi, Nadal, Federer and Djokovic are the only male players since Borg to have won the French Open and Wimbledon men's singles titles over their career. Ilie Nastase once said about Borg, "We're playing tennis, and he's playing something else".  In his 1979 autobiography, Jack Kramer, the long-time tennis promoter and great player himself, had already included Borg in his list of the 21 greatest players of all time. And in 2003, Bud Collins chose Borg as one of his top-five male players of all time.  In 2008, ESPN.com asked tennis analysts, writers, and former players to build the perfect open era player. Borg was the only player mentioned in four categories: defense, footwork, intangibles, and mental toughness--with his mental game and footwork singled out as the best in open era history.  Borg famously never won the US Open, losing in the final four times. Borg also never won the Australian Open, as he only played in the event once, in 1974 as a 17-year-old. The only players to defeat Borg in a Grand Slam final were fellow World No. 1 tennis players John McEnroe and Jimmy Connors. Even though it was then played on grass, a surface where he enjoyed much success, Borg chose to play the Australian Open only once, in 1974, where he lost in the third round. Phil Dent, a contemporary of Borg, has pointed out that skipping Grand Slam tournaments--especially the Australian Open--was not unusual then, before counting Grand Slam titles became the norm. Additionally, another contemporary Arthur Ashe told Sports Illustrated, "I think Bjorn could have won the U.S. Open. I think he could have won the Grand Slam, but by the time he left, the historical challenge didn't mean anything. He was bigger than the game. He was like Elvis or Liz Taylor or somebody."

Using a quote from the above article, answer the following question: What was Borg recognized for?
With 11 Grand Slam titles,