Marsh was sacked on Wednesday, just three months into a two-year contract.
Colombo: Sri Lanka's cricket chief defended the sacking of Australian coach Geoff Marsh and the selection of a new team captain, saying the changes would help usher in a new era of "cricketing excellence."
"We will reap the benefits of these changes in the fullness of time," Sri Lanka Cricket president Upali Dharmadasa said in statement on Friday.
The sacking of Marsh on Wednesday - just three months into a two-year contract - was widely criticised, with former team skipper Arjuna Ranatunga calling the move "disgraceful" and "unprofessional."
Marsh was replaced by South African Graham Ford, who becomes Sri Lanka's fourth coach since Australian Trevor Bayliss stepped aside after the World Cup final in April 2011.
While voicing gratitude for Marsh's efforts, Dharmadasa said it was time for Sri Lankan cricket to "move on."
"The appointment of Ford was "based on the fact that he can cope with the demands a 21st-century coach has to cope with in the international arena," the statement said.
The change in coaches came two days after Tillakaratne Dilshan quit as team captain, to be replaced by former skipper Mahela Jayawardene.
"This change will also help Dilshan to concentrate more on his game," Dharmadasa said. "We strongly believe Dilshan's contribution will be much more if he is relived of additional responsibility. This will help the team's overall performance."
Sri Lanka's Sports Minister last week named a four-member selection panel and gave them one year to put the team in order after the side lost Test and one-day series to England, Australia, Pakistan and South Africa recently.