Hello Raghavendra,
No this is not a possibility, you cannot directly participate in mop up round without participating in Round-1 or Round-2.
All the unfilled seats are filled in the mop up round and students who failed to be allotted any college in Round-1 & 2 can also get colleges in the mop up round.
So you need to register in the counselling rounds before in order to go for mop up round.
Hope this helps.
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