Alastair Cook has scaled a summit that 623 England players who made their Test debut before him couldn't. By reaching 10,000 Test runs, he joins a pantheon of batsmen as the youngest among them to reach that milestone. Tendulkar - the quickest before Cook - had scored his 10,000th run at the age of 31 years and 327 days. Cook has taken 170 days fewer than him. He is also the quickest from debut - by over a year - to get there, having taken just ten years and 88 days.

England's predilection for Test cricket - they have played an average of 12.5 Tests a year since Cook's debut, more than any other team - has obviously helped Cook in getting there quicker than any other batsman. However, to his credit, Cook has both kept himself fit and kept his contributions - with the bat and the captaincy - significant enough to play in 128 of the 129 England Tests since his debut. In fact, he has played in 126 consecutive Tests since his one and only absence - he missed the third Test of his debut tour to India in 2006 due to a stomach bug. That is the second-longest continuous streak by any player for any Test team. Only Allan Border's streak of 153 consecutive Tests for Australia is longer than Cook's.

Besides his patience and determination, Cook's fitness is one of the key reasons for his huge tally of runs, for he doesn't score quickly and so has to stay on the field longer to get them. Among batsmen with at least 5000 runs since the turn of the century, Cook's strike rate is the third lowest. Right from the start of his Test career Cook has preferred to dig in to score runs - as a 21-year-old on debut in Nagpur, he made a 243-ball unbeaten 104 in the second innings. Since then, there have been 30 more innings of at least 200 deliveries. The last of those came against Pakistan in Abu Dhabi when Cook batted 836 minutes for a 528-ball 263 - the third longest individual innings of all time.

These marathon innings demand patience, and Cooks clearly has it in spades. The one aspect of his batting that epitomises this is his ability to leave the ball. By the end of the Chester-le-Street Test against Sri Lanka, Cook had offered no shot to 4,465 deliveries, which is 20.6% of the balls he has faced in his career. In terms of percentage of balls faced since Cook's debut, only Shivnarine Chanderpaul has left alone a higher share of deliveries among modern batsmen in the 10,000-club.

Highest percentage of balls left in Tests since Cook's debut
Batsman Deliveries left alone Deliveries Faced %age
 Shivnarine Chanderpaul  2788  13062  21.34
 Alastair Cook  4465  21658  20.62
 Jacques Kallis  2256  11134  20.26
 Sachin Tendulkar  1829  10193  17.94
 Kumar Sangakkara  2659  15554  17.10

Cook is eighth on the list of batsmen who have faced the most deliveries in Tests in the last 20 years. He has faced an average of 94.57 deliveries per innings, which is the sixth highest by any batsman with a cut-off of 100 innings.

What stands out, though, is Cook's ability to construct these marathon innings in Asia - conditions that have usually challenged non-Asian batsmen. Cook has batted an average of 122.8 deliveries per innings in subcontinent conditions (including the UAE) which are the highest for any batsman, Asian or otherwise, to have played at least 30 innings in the last 20 years.

Most deliveries per innings in Asia since 1996 (min 30 inns)
Batsman Balls faced in Asia Inns Balls/Inns
 Alastair Cook  5035  41  122.80
 Azhar Ali  6208  53  117.13
 Hashim Amla  4195  39  107.56
 Jacques Kallis  4672  44  106.18
 Rahul Dravid  16856  160  105.35

Cook' 2,252 runs in Tests in Asia are the most by any overseas batsman. Jacques Kallis is the only other batsman to aggregate 2,000 runs. Among the 63 non-Asian batsmen who have scored at least 5,000 Test runs, Cook's 22.4% runs in Asia are the third highest contribution to career runs after Hashim Amla's 24.7% and Carl Hooper's 23.8%.

Top %age of runs scored in Asia, overseas batsmen (min 5000 Test runs)
Batsman Runs in Asia Career Runs %age
 Hashim Amla  1819  7358  24.72
 Carl Hooper  1373  5762  23.82
 Alastair Cook  2252  10042  22.42
 Marcus Trescothick  1306  5825  22.42
 Stephen Fleming  1571  7172  21.90

Cook's game is at its dogged best in his back-to-the-wall second-innings efforts, such as the ones at the Gabba, in Ahmedabad, and in Galle. His second-innings numbers don't look extraordinary on the outset - 3,952 runs at 44.40 with 13 hundreds. But nine of those 13 hundreds have come with England facing a second-innings deficit. Only Sachin Tendulkar has made more centuries while trailing in the second innings. Sunil Gavaskar, Kumar Sangakkara and Brian Lara too made nine such centuries, but in 75, 83 and 93 innings, respectively, to Cook's 72. Cook has made 2,942 runs in second innings when faced with a deficit, which is 29.30% of his career runs. This is the second highest for any batsman in the 10,000-club after Gavaskar, who made 33.65% of his career runs when facing a second-innings deficit.

Most centuries facing deficit in second innings
Batsman Inns Runs Ave 100s %age runs
 Sachin Tendulkar  113  3649  46.18  11  22.91
 Alastair Cook  73  2942  47.45  9  29.29
 Sunil Gavaskar  75  3406  55.83  9  33.64
 Kumar Sangakkara  83  3248  50.75  9  26.19
 Brian Lara  93  3224  39.31  9  26.97

The quality of stubborn resilience that Cook has displayed in bailing out England on so many occasions has helped in his career too. Starting in 2013, he hit a rough patch in which he managed just 638 runs at 23.62 and went without a century for 27 innings. But, with the clamour for dropping him as England's Test captain at its loudest following England's loss to India at Lord's in 2014, Cook made use of the luck that came his way in the next Test in Southampton to score 95 and 70 not out. His next hundred took another eight innings to come, but Southampton marked a revival in Cook's batting career: in 30 innings beginning with that Test, Cook scored 1,625 runs at an average of 58.03 with three hundreds and 11 fifties. In the subsequent year, Cook scored 1,364 runs at 54.56 - the fourth highest by an England batsman in Tests in calendar year.

Cook has scored 900 or more runs in a calendar year eight times already in only ten complete years of his Test career. One could argue that's not a big achievement considering he gets to bat enough every year to get there. But in six of those years he has averaged at least 45. Only two other batsmen - Tendulkar and Kumar Sangakkara - have had seven years when they have scored 900-plus runs at an average of at least 45. Admittedly though, batsmen from Asia do not play as many Tests every year as those from England or Australia. But the next best England batsmen in this list are Andrew Strauss, Kevin Pietersen and Mike Atherton who had three such years each in their careers that lasted eight, nine and 12 years respectively. Ricky Ponting is the nearest Australia batsman to Cook in this roster, with five such years in a career spanning 17 years.

900-plus runs at 45-plus average in a calendar year
Batsman Years Career span
 Kumar Sangakkara  7  15
 Sachin Tendulkar  7  24
 Alastair Cook  6  10
 Brian Lara  6  16
 Rahul Dravid  6  16
 Jacques Kallis  6  18

Cook is only the second regular opener after Sunil Gavaskar to make it to the 10,000-club. In all likelihood, he will be the first batsman to get 10,000 Test runs purely as an opener too: Cook needs 536 more runs to get there and 144 to go past Gavaskar as the highest run-scorer among openers in Test history.

He has ticked most of the boxes that batsmen who have long careers usually do. Cook is one of the only 12 batsmen to make centuries against all the eight (or nine) teams he has played against. He just needs five more runs against South Africa to become only the third batsman - after Tendulkar and Dravid - to make 1000 runs against seven Test teams. He has also hit at least one Test hundred in all the nine cricketing countries he has played in. The fact that only one batsman in Test history has managed that in more countries than him - Dravid hit centuries all the ten countries he played in - should confirm Cook as one of the most adaptive batsmen in Test history.

Shiva Jayaraman is a senior sub-editor (stats) at ESPNcricinfo.com. @shiva_cricinfo