Muralitharan's Test career is under threat after he was no-balled seven times for throwing on the opening day of the second Test against Australia. Sri Lanka are considering omitting him from next month's third Test and sending him home unless the International Cricket Council makes a definite ruling over his suspect bowling action.
Richardson, whose West Indies side played Sri Lanka earlier this month in the World Series limited-overs tournament in Australia, said he did not believe the spinner was a "chucker", merely unorthodox.
"When I look at the slow motion picture of him bowling, I don't really think he chucks. He comes over with a slightly bent arm and when he releases the ball his wrist straightens, but if you look really carefully the arm remains bent," the West Indian captain said.
Border, who retired from Test cricket last year, admitted: "I just feel sorry for this young bloke and I think he's been set up a little bit.
"If they decide he's legal, let him play out his career because he's played 23 Tests to date and hasn't been called before."
Richardson also questioned the sudden decision to no-ball Muralitharan. "I don't want to criticise the umpire but if he's chucked that one he has thrown many more," he said.
The controversy and confusion lingered into the second day of the Test when Muralitharan bowled a further 20 overs without being no-balled.
Muralitharan was bowling from the Southern End of the MCG when he was no-balled on Tuesday by Darrell Hair but he survived subsequent scrutiny after switching to the Members' End, where Steve Dunne, the umpire from New Zealand, was standing.
The Sri Lanka management said they would talk to both umpires at the end of the match in an attempt to establish why some of Muralitharan's deliveries were called while others were deemed legitimate.
Hair, who made all the calls against him, told Sri Lankan officials he would no-ball him again if Muralitharan bowled during the final session of the second day on Wednesday, but Muralitharan did not bowl again in the innings even though Australia made 500.
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