Ganguly made his One Day International (ODI) debut for India against West Indies in 1992 scoring just 3 he was dropped immediately. He returned to International cricket four years later, following a good domestic record, he was recalled into the national side for a Test series in England. He made his Test debut at Lord's, scoring a century he became only the third cricketer to score a century on debut at Lord's, after Harry Graham and John Hampshire. (Andrew Strauss has also since accomplished this feat). In the next Test match at Trent Bridge he scored another century, 136, sharing in a 255 run stand with Sachin Tendulkar.
In 1997 Ganguly scored his maiden ODI century, opening the innings he scored 113, in his side's 238, against Sri Lanka later that year he won four consecutive Man of the match awards in the Sahara Cup with Pakistan the second of these was won after he took 5/16 off 10 overs, his best bowling in a ODI. After a barren run in Test cricket his form returned at the end of the year with three centuries in four Tests all against Sri Lanka two of this involved 250+ stands with Sachin Tendulkar.
In January 1998, he had one of his most memorable performances in the final of the Independence Cup at Dhaka against Pakistan he scored 124 as India successfully chased down 315 off 48 overs, winning the Man of the match award. In March 1998 he was part of the India team that beat Australia his biggest impact came in Calcutta as he took three wickets having opened the bowling with his medium pace.
In the 1999 World Cup Ganguly smashed 183 against Sri Lanka at Taunton, the innings took 158 balls and included 17 fours and 7 sixes. It is the second highest in World Cup history and the highest by an Indian in the tournament. His partnership of 318 with Rahul Dravid is the highest ever in the World Cup and is the second highest in all ODI cricket.
In 1999/00 India lost series to both Australia and South Africa in the five Tests Ganguly struggled scoring 224 runs at 22.40. However his ODI form was impressive with five centuries over the season taking him to the top of PwC One Day Ratings for batsmen.[8]
In 2000, after the match fixing scandal Ganguly was named the captain of the India team. In the Champions Trophy of that year he scored 2 centuries but his second in the final was in vain as New Zealand won by four wickets.
In 2003 under his captaincy India reached the World Cup Final, where they lost to the Australians.
While he has achieved significant success as captain, his individual performance deteriorated during his captaincy, especially after successes in the World Cup, the tour of Australia in 2003 and the Pakistan series in 2004. Following indifferent form in 2004 and poor form in 2005, he was dropped from the team in October 2005. He remained active on the first-class cricket scene in hopes of a recall, but his performance was a mixed bag - he hit a couple of centuries in domestic cricket, but his English county stint in 2005 and subsequent appearances in the Challenger Trophy were failures.
Ganguly has 22 centuries in ODIs, in terms of number of centuries in ODIs, he is only behind [9] Sachin Tendulkar, Sanath Jayasuriya and Ricky Ponting. Sourav, along with Sachin Tendulkar, formed by far the most successful opening pair in One Day Cricket, having amassed the highest number of century partnerships (26) for the first wicket. Together, they have scored more than 7000 runs at an average of 48.98, now with Sachin he is a world record holder for creating most no. of 50 run partnership in the first wicket(44 fifties) [10].
Ganguly is the fourth player to cross 11,000 ODI runs and third player to cross 10,000 ODI runs and so far the fastest in ODI history, after Sachin Tendulkar. He also reached 6000, 7000, 8000 and 9000 ODI runs milestones in the fewest number of matches. Sourav can bowl medium-pacers as well, but has under-achieved in this aspect in Test matches, taking 31 wickets in 99 matches, at an average of 52.47. As of 2006, he is the only Indian captain to win a Test series in Pakistan (although two of the three tests of that series was led by Rahul Dravid). He is also one of the 3 players in the world to achieve amazing treble of 10,000 runs, 100 wickets and 100 catches in ODI cricket history, the others being Sachin Tendulkar and Sanath Jayasuriya.
In 2004, he was awarded the Padma Shri.
His older brother Snehasish Ganguly played first-class cricket for Bengal.
Ganguly's international cricket career could be bisected into 2 halves, the pre and the post Y2K eras. The significance of the year 2000 lies not only in the fact that he became the captain of the Indian team but also in the fact that the ICC introduced the one bouncer per over rule in ODIs starting from that year. This introduction of the rule by the ICC had a negative impact on Sourav Ganguly's batting average, which plunged from a high 45.5 before the year 2000 to a low 34.9 between the 5 year period of 2001-2005 [11]. Also, against Test playing nations (which included Zimbabwe and Bangladesh), his overall average plunged further down to 30.66, as did his 'away' average which fell to 29. He managed to score only (6) centuries between 2001-2005, of which 3 centuries were against Kenya & 1 was against Namibia.[12] This sudden drop in his batting average against Test playing nations after 2001 was clearly a result of the short pitched bowling he had to encounter from opposition bowlers. As S.Rajesh, the assistant editor of Cricinfo analyzes, Ganguly has been dismissed numerous times fending off the short ball.[13]
Also, Ganguly's Test career had been riddled with lean patches, the first of which stretched for 3 years from Dec 1999 to Dec 2002 [14], during which his batting average fell to 31.77 in 36 consecutive Test matches over 60 innings. The next biggest lean patch of his career occurred after the 2003 World Cup, when his ODI average fell to 28 and this was when his place in the team was questioned by numerous Indian cricket fans. He averaged 24.95 in 25 ODI matches between August 2004 and September 2005 [15], before being finally dropped from the ODI side.
Despite his hot and cold streaks Ganguly is only the third Indian Test match batsman to maintain a career average that never dipped below 40 runs per innings for his entire Test career. The other two who achieved this feat are Sunil Gavaskar and Mohammad Azharuddin.
Ganguly also shares with G.R. Viswanath the Indian record for scoring at least 10 or more centuries and never being on the losing side in every match in which they had scored a century. He also shares with Mohammad Azharuddin the record of scoring two consecutive hundreds in his first two Test matches, though Azharuddin bettered that by scoring a third consecutive hundred in his third Test match.
Ganguly has the highest Test and ODI aggregate of any left-handed batsman India has produced and his 13 Test and 22 ODI centuries are also a record for any Indian left-hander.
It was, however, as captain of the Indian team that Ganguly's biggest achievements occurred. He led India in 49 Test Matches, winning 21 of those, including 12 of them outside India. All three figures are records for Indian Test captains. He also led India to their first series wins in both Tests and ODIs in Pakistan, a feat that had eluded India for over 50 years. Ganguly also led India to more Test wins (12) outside India between 2000 and 2005 than all Indian captains had done between 1980 and 2000. He led India to victory over Steve Waugh's Australia in the 2001 Border-Gavaskar trophy which is considered one of the greatest in Indian cricket history.
Rahul Dravid once commented, "On the off-side, first there is God, then there is Ganguly”.