World Twenty20 hero Shahid Afridi believes Pakistan will face a tough challenge in the upcoming Test series against Sri Lanka.

Afridi, who steered Pakistan to victory in the final of the World Twenty20 last month, opted out of the Test series which begins in Galle on Saturday in order to rest. The all-rounder believes the conditions in Sri Lanka will offer a tough prospect compared to England.

"It will not be easy for the players to shift focus from Twenty20 to Test cricket," Afridi said.

He added: "Sri Lanka are tough opponents at home and the conditions will be very different from England.

"For us to beat them, every player will have to give 100%."

Afridi, who will return for the one-day series which follows the three Tests, was though critical of the timing of the series.

"There should have been a longer gap in the schedule so that the players could have prepared for the series better," Afridi said.

"They haven't had time to enjoy their win in the World Cup and were at home for just three days.

"They haven't had time to relax and prepare sufficiently for the series."