Not since West Indian Brian Laras exploits in Galle in 2001 when he scored 688 runs in six innings, had a batsman played spin bowlers so expertly. Root now has 415 runs in three innings.
The sweep shot was Roots bread and butter and he executed it to perfection, finding gaps frequently despite Sri Lana having three fielders in the leg-side boundary.
The 30-year-old reached his 19th test hundred in the morning and during his knock went past the run tallies of three former England greats David Gower 8,231, Kevin Pietersen 8,181 and Geoffrey Boycott 8,114.
Root, playing in his 99th test match, now has 8,238 test runs and is fourth among England batsmen.
Apart from Embuldeniya, the rest of Sri Lankas bowling failed to impress, with off-spinner Dilruwan Perera failing to pick up a wicket despite the 38-year-old bowling 32 overs.
England resumed from the overnight score of 98 for two and lost Jonny Bairstow (28) and Daniel Lawrence (3) early. Vice-captain Jos Buttler (55) added 97 runs for the fifth wicket with Root.
An 81-run stand for the seventh wicket between Dominic Bess (32) and Root took Englands total to 333 for six. But Sri Lanka struck back, taking three wickets for six runs late in the day to reduce the tourists to 339 for nine.
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