When Muttiah Muralitharan retired from Test cricket in July 2010, it was assumed that Sri Lanka would never be able to replace him.
That assumption was reasonable back then. Muralitharan had retired with an astounding 800 wickets in 133 Tests, at an average of 22.72. At the time, the next-highest wickets tally for a specialist spinner from Sri Lanka was 71, by a bowler named Rangana Herath. (Sanath Jayasuriya had 98, but he wasn't a specialist spinner.) The left-arm spinner was averaging 37.88 in 22 Tests and was already 32 years old. It was hardly believable that he - or any other bowler - could come close to being as effective as Muralitharan had been for Sri Lanka.
Fast forward eight years. Herath has achieved so many feats and has led Sri Lanka to so many wins, that a comparison with Muralitharan is not only warranted, but perfectly justified. In 70 Tests since Muralitharan's retirement, Herath has picked up 359 wickets at an average of less than 26, with 30 five-wicket hauls.
A comparable period for Muralitharan would be from 2001 till his retirement, when he played 75 Tests. In those matches, he took an astounding 498 wickets at 21.23. While that is quite a bit better than Herath's numbers, 133 of those wickets came from just 16 Tests against the relatively weaker batting line-ups of Bangladesh and Zimbabwe, at a stunning average of 12.80.
Exclude the stats against those two teams for both bowlers, and the numbers are much closer. Muralitharan still took more wickets , but the difference in averages is much smaller, and the gap in strike-rates is negligible. Also, Herath won more Man-of-the-Match awards against the top teams. Muralitharan, though, bowled a lot more than Herath, averaging 59 overs per Test to Herath's 47.3. He also took a higher percentage of the team's wickets - 42% to 32% - and bowled a higher percentage of their overs - 35% to 29%.
Both bowlers had one Man-of-the-Match performance overseas in the periods mentioned above - Muralitharan at Trent Bridge in 2006, and Herath in Durban in 2011 - but it was in home Tests that they really turned it on. In Sri Lanka, there is little to choose between the two in these periods: Muralitharan's average was marginally better, but Herath needed five fewer balls per wicket, and also won one extra Man-of-the-Match award despite playing four fewer home Tests.
With numbers like these, it's clear that Herath has done an outstanding job of replacing Muralitharan. Now, all of Sri Lanka will hope that someone will similarly come along and take the baton from Herath.
Herath was at his most threatening in the fourth innings of Tests, and his numbers make him arguably the finest fourth-innings bowler in Test history.
He has bowled 40 times in the fourth innings of Tests; on 12 of those instances he took at least five wickets; 16 times he took at least four; only three times did he bowl 15-plus fourth-innings overs and went wicketless.
His 12 five-fors is easily the best; the next-best is seven, by Muralitharan and Shane Warne. His average of 18.08 is third among the 20 bowlers with 50-plus fourth-innings wickets; only Bishan Bedi and Curtly Ambrose have done better. And in terms of wickets, only Warne (138) has more fourth-innings wickets than Herath's 115.
In first innings of Tests, Herath has averaged 36.48, which means his average in the last innings is half the first-innings number. In comparison, Muralitharan was clearly better in the first innings - he averaged 26.47 - but even he wasn't as deadly in the fourth innings, averaging 21.01.
Against the top eight teams in the period after Muralitharan's retirement, Herath's fourth-innings average dropped further to 17.70 compared to Muralitharan's 20.43 against the top teams in the 2001-2010 period. Further, Herath's strike rate of 43.8 was significantly better than Muralitharan's 50.3 in this period.
These numbers suggest that, in certain conditions, batsmen might have preferred facing Muralitharan to Herath. Can there be a bigger compliment than that for any spinner?