Question: Ivan Lendl and Ken Rosewall, have which occupation in common?
Context: American tennis player Pancho Gonzales had a long-running rivalry with Australian Ken Rosewall.  Gonzales is still sometimes considered to be a candidate for the greatest tennis player of all time; he was the dominant player of the 1950s and still holds the men's all-time record of being ranked world No. 1 for eight years.  Rosewall became the world's best player upon Gonzales's semi-retirement in 1961 and held that position either by himself or sharing it with others for six years.  Rosewall was signed in 1956 by the promoter Jack Kramer, a former #1 player himself, to join his small band of touring professionals in 1957.  He then engaged in a round-the-world, head-to-head tour against Gonzales, the defending world's champion, over the next five months, winning 26 matches but losing 50.  In his 1979 autobiography Kramer included both Gonzales and Rosewall in his list of the 21 greatest players of all time.  Kramer, however, initially "panicked" upon signing Rosewall.He was a cute little fellow with a dink serve, who operated mostly from the baseline.  That great volley of his hadn't been developed yet.  I was afraid that Gorgo would eat him alive and put us out of business the rest of the way.  But like a lot of people I completely underestimated Rosewall.  Before their opening match in Melbourne, Kramer went to Gonzales and asked him to "carry" Rosewall, giving him a better share of the gate to gain his assent.  Gonzales did try to carry out his part of the deal for a few matches, but then called it off, telling Kramer that he was no longer able to play his normal game.  Kramer agreed.  "It was... obvious that Rosewall was not the pushover I had feared.  (In fact, Gonzales only beat him 50–26, and it was always competitive.)"  Six years older than Rosewall, 13 years later, in 1970, Gonzales defeated him in 6–4, 6–4, in the 199th and next-to-last match they ever played—Gonzales was 42 years old at the time and Rosewall was considered to be the co-No.  1 player in the world. Fausto Gardini (8 March 1930 – 17 September 2008) was an Italian tennis player.  He was an Italian Davis Cup player and later captain.  Gardini had long arms and legs, was renowned for keeping the ball in play and was very determined.  "I could not help but admire Gardini because he always tried" said Ken Rosewall.  This is how William McHale described Gardini "A stringy, expressive, cavorting clown, Gardini uses the crowd as his personal cheering section".  Gardini made his Grand Slam debut at Roland Garros in 1949, where he lost in round three to Eric Sturgess.  At Roland Garros in 1951, Gardini lost in the last 16 to Dick Savitt.  At Wimbledon Gardini beat Gardnar Mulloy before losing to Frank Sedgman in the last 16.  At Roland Garros in 1952, Gardini beat 17 year old Ken Rosewall and Tony Mottram before losing to Jaroslav Drobny in the last 16.  At Wimbledon he lost to Straight Clark in round three.  At the 1953 Australian championships, Gardini lost in round two to Ian Ayre.  At Roland Garros, Gardini reached the quarter finals before losing to Drobny.  At Wimbledon he lost in round one to Istvan Sikorski.  The highlight of Gardini's career was when he won the title at Rome in 1955, beating Herbert Flam, Enrique Morea and Giuseppe Merlo.  The final was a dramatic match.  Merlo led by 2 sets to 1 and had two championship points in the fourth set, but suffered from cramps and was forced to retire at 6-6 in the fourth set.  After that, Gardini played less and concentrated on running his family's bakery business.  By the early 1960s he was playing mainly in Italian tournaments and Davis Cup. The tennis players Ivan Lendl (Czechoslovakia, 1978–92/United States, 1992–94) and Mats Wilander (Sweden) met 22 times during their careers.  Lendl leads their overall head-to-head series 15–7. This was a tennis rivalry between Czech Ivan Lendl, and American John McEnroe, who met in their careers 36 times between 1980 and 1992.  They met 37 times in official matches, and over 60 times when invitational tournaments and exhibition events are included.  It is one of the most notable tennis rivalries of the open era.  Their most memorable match was in Roland Garros in 1984, when Lendl came from two sets down to win the final. Kenneth Robert Rosewall {'1': ", '2': ", '3': 'AM, MBE', '4': "} (born 2 November 1934) is a former world top-ranking amateur and professional tennis player from Australia.  He won a record 23 tennis Majors including 8 Grand Slam singles titles and before the Open Era a record 15 Pro Slam titles and a record 35 Major finals overall.  He won the Pro Grand Slam in 1963.  Rosewall won 9 slams in doubles with a career double grand slam.  He is considered to be one of the greatest tennis players of all time.  He had a renowned backhand and enjoyed a long career at the highest levels from the early 1950s to the early 1970s.  Rosewall was one of the two best male players for about nine years and was the World No. 1 player for a number of years in the early 1960s.  He was ranked among the top 20 players, amateur or professional, every year from 1952 through 1977.  Rosewall is the only player to have simultaneously held Pro Grand Slam titles on three different surfaces (1962–1963).  At the 1971 Australian Open he became the first male player during the open era to win a Grand Slam tournament without dropping a set. This is a list of the main career statistics of Australian former tennis player Ken Rosewall whose playing career ran from 1951 until 1978.  He played as an amateur from 1951 until the end of 1956 when he joined Jack Kramer's professional circuit.  As a professional he was banned from playing the Grand Slam tournaments as well as other tournaments organized by the national associations of the International Lawn Tennis Federation (ILTF).  In 1968, with the advent of the Open Era, the distinction between amateurs and professionals disappeared and Rosewall was again able to compete in most Grand Slam events until the end of his career in 1978.  During his career he won eight Grand Slam, 15 Pro Slam and three Davis Cup titles. Ivan Lendl (] ; born March 7, 1960) is a retired tennis player originally from Czechoslovakia who became a United States citizen in 1992.  He is often considered among the greatest in the sport's history.  He was the world No. 1 for 270 weeks in the 1980s and finished his career with 94 singles titles.  At the majors he won eight titles and was runner-up a record 11 times.  He also won seven year-end championships and a record 22 Grand Prix Super Series titles. Australian tennis player Rod Laver (born 1938) had a long-running and friendly rivalry with countryman Ken Rosewall (born 1934).  In 1956 both players toured in the amateur circuit but never faced each other.  Rosewall turned professional in 1957 and the two players did not meet until January 1963 when Laver turned pro.  They played many times until 1977 when both semi-retired from the main tour. The Connors–Lendl rivalry was a tennis rivalry played between American Jimmy Connors and Czech-American Ivan Lendl, who met 35 times.  Connors, who is 7 and a half years older than Lendl, won the first 8 matches, while Lendl won the last 17 and ended up leading the rivalry 22–13. Peter Feigl (born 30 November 1951) is a former Austrian professional tennis player.  He was a quarter-finalist in the 1978 Australian Open defeating Ken Rosewall in what would be Rosewall's final grand slam match.
Answer: tennis player