The 23-year-old spinner strained his right hamstring during the Asia Cup Super Four clash against Pakistan and subsequently missed the final against India. Theekshana was named in Sri Lanka’s World Cup squad despite not recovering from the injury but was expected to be fit in time for the opening game against the Proteas.

He did not travel with the Sri Lanka team to India, on September 26, and was expected to fly down on October 3.

But a day before the team begin their campaign in the event, Theekshana has been ruled out of the clash, massively weakening the side’s spin department, with all-rounder Wanindu Hasaranga also absent due to a hamstring injury. Hasaranga has not been picked in the World Cup squad, and will only be selected as a replacement player if he gets fit before the event ends.

Theekshana has taken 44 wickets in 27 games at an average of 23.45, which falls to 17.45 this year. Along with Hasaranga, Theekshana has proved lethal in the middle overs, and their absence will be a huge miss.

Sri Lanka will also be without 31-year-old quick Dushmantha Chameera for the World Cup after he did not recover in time from a torn pectoral muscle. Lahiru Kumara and Dilshan Madushanka, who were injured for the Asia Cup, have been picked in the World Cup squad after passing fitness tests.