Money deposit above rs 20,000 to client's bank account ?

YES IT WILL BE DISALLOWED AS PER 40(A)(3), IF CLIENT DOESNT FALL IN RULE 6DD

As per Section 40A(3) you have to pay an amount exceeding 20000 by way of a/c payee cheque or DD,
So direct deposit to client's account will be disallowed u/s 40A(3)..

As per my opinion your client should make book adjustments ie fund transfer from his bank a/c to supplier's bank a/c as it will be covered under exceptions to 40A(3)[ Rule 6DD].

Yes, I Agree with both Kunal and Nuba.