In 2010 Sock won the individual competition at the US Junior Open . He started as a professional the same year he played with a wildcard in the main draw of the US Open . He lost to Marco Chiudinelli and was ranked 878th in the world at the end of the season. In 2011 he also received a wildcard for the Miami Masters and again for the US Open . In his second Grand Slam appearance , he achieved his first victory with a 3-1 win over Marc Gicquel . In the second round he was clearly defeated by Andy Roddick in three sets. While he was eliminated in the first round in the doubles competition, he managed one of the biggest surprises of the tournament in mixed together with Melanie Oudin . Equipped with a wildcard, they defeated the defending champions and huge favorites Liezel Huber and Bob Bryan in the round of 16 with 6: 2, 3: 6, [10: 6]; it was followed by a smooth two-set victory over Barbora Záhlavová-Strýcová and Philipp Petzschner and a fight-free progress against Jelena Wesnina and Leander Paes . In the final, Oudin and Sock met the Argentinians Gisela Dulko and Eduardo Schwank , who were seeded in 8th position, and narrowly defeated them 7: 6, 4 , 4: 6 and [10: 8]. For the US Open 2012 , Sock received his third wildcard in a row. By reaching the third round in singles and round two in doubles, he achieved his best result so far in both competitions.
At Wimbledon in 2014 he won the doubles competition with Vasek Pospisil as an unseeded pairing. They defeated four of the eight best doubles pairings, including Bob and Mike Bryan in the final , which they defeated in five sets. Sock and Pospisil soon won the Atlanta tournament and reached the Cincinnati final . In Cincinnati they clearly defeated Bob and Mike Bryan in two sentences. At the side of Treat Huey , Sock reached another final of a doubles competition in Stockholm . In October he was in the top 50 in singles for the first time, while in doubles he achieved his highest ranking to date with 13th place.
In April 2015 he won his first tournament on the ATP World Tour with the US Men's Clay Court Championships . In the final he defeated his compatriot Sam Querrey . In Stockholm he reached another final, which he lost to Tomáš Berdych . In doubles he won two titles with Vasek Pospisil, including the Masters in Indian Wells . In addition, the two were in the final of the Masters tournaments in Miami and Paris . He won a third double title with Nicholas Monroe . In May 2015 he reached 6th place in the double world rankings.
Jack Sock started the 2016 season in good form and reached the final in his first tournament in Auckland , in which he had to retire due to injury. In Houston and Stockholm, too, he only had to admit defeat in the final. At the Grand Slam level, he managed to reach a round of 16 at the US Open for the second time after the French Open last year, after being ranked 9th in the world in the third round. Marin Čilić struck. There he was defeated by the Frenchman Jo-Wilfried Tsonga in four sentences. He finished the year in 23rd place, his best result at the end of the year.
In 2017 he improved his result from the previous year in Auckland and won there against João Sousa in the final . After another tournament victory in Delray Beach , where he benefited from Milos Raonic's non-appearance in the final , he also impressed at an ATP World Tour Masters 1000 . At the Sunshine Double he was in Indian Wells first in the semi-finals and in the following week in Miami in the quarter-finals. The season's high-flyers, Roger Federer and Rafael Nadal , were each the final destination. After less good results at the Grand Slam tournaments, Sock celebrated his greatest success just before the end of the season. At the Masters in Paris he played - only in 16th place - in the final against another surprise finalist and qualifier Filip Krajinović and won in three sets after the favorites had all failed early. This meant that he was qualified for the ATP Finals for the first time . Here he surprised again with wins against Čilić and Alexander Zverev and reached the semi-finals, where he had to admit defeat to the eventual tournament winner Grigor Dimitrov . He ended the year at his career high, 8th in the world rankings.
In 2018 he won the doubles competition at Wimbledon again alongside Mike Bryan , whose brother Bob had previously been injured at the French Open . In mixed he reached the round of 16 with Sloane Stephens . He was also able to win the doubles competition at the US Open and the ATP Finals in London for the first time with Mike Bryan . So Sock ended the year as second in the world rankings in doubles. The year was much more disappointing in individual terms. Only at the Masters in Paris did he win more than one match when he started as defending champion. As a result, he fell out of the top 100.