Sri Lankan police questioned skipper Angelo Mathews the previous day as part of investigations into an attempt to bribe players to under-perform in a Test match against the West Indies.
"All allegations have to be investigated in fairness to the players and in fairness to the Sri Lankan team and to Sri Lanka," the prime minister said when asked about the cricket probe at a news conference during an annual gathering of billionaires and political leaders in the Swiss ski resort of Davos.
"This is about a player approach, no investigation against any of the cricketers," Mathews said.
Sri Lanka beat the tourists by an innings and six runs after veteran left-arm spinner Rangana Herath took 10 wickets.
On Monday the Sri Lanka cricket board suspended its fast bowling coach Anusha Samaranayake for two months and sacked a part-time employee, net bowler Gayan Vishwajith, during an investigation into the bribery allegations.
