Bangladesh will benefit in the long term from facing Afghanistan's daunting spin attack in the ongoing three-match one-day series, assistant coach Nic Pothas said Monday.

Afghanistan won the first two matches to become only the second team to win an ODI series in Bangladesh in the past seven years, the other being world champions England.

"They have the best spin attack in the world -- that's just a fact," Pothas told reporters in Chittagong of the tourists.

Spinners Mujeeb Ur Rahman, Rashid Khan and Mohammad Nabi contributed heavily to the wins in the first two matches, sharing 11 wickets among them.

"No other team in the world has three spinners of this quality that keep coming at you all the time," said Pothas.

"It will make us better. If you can face this level of spin, you can face anybody," he added, with the World Cup on the horizon in October.

The third match is on Tuesday, when Bangladesh risk being whitewashed at home for the first time since a 3-0 defeat to Sri Lanka in 2014.

Bangladesh's batsmen struggled against the spin trio in both matches so far, making 169-9 and 189 all out respectively.

Afghanistan's bowling coach Hamid Hassan also praised left-arm pacer Fazalhaq Farooqi, who earned crucial breakthroughs in both matches and picked up six wickets.

"Hopefully in the Asia Cup, and we're targeting the World Cup, he'll be our man and the key bowler," said Hassan.

Following the ODI series are two T20s in Bangladesh's northeastern city of Sylhet on July 14 and 16.

Bangladesh and Afghanistan open their World Cup campaigns against each other on October 7 in India.