According to Prasad, it might be a good idea to have at least a 26-strong squad for the tour Down Under where both India and the 'A' team could be clubbed together for a month.
Pakistan are travelling with a squad of 29 (including white-ball specialists) while the West Indies have 26 on their roster in order to maintain the COVID-19 protocols in England.
"The team management and seniors will have an opportunity to look at the youngsters who are knocking the doors," Prasad, who till February was selection committee head, told PTI during an interaction.
"In this process, you can also monitor those players who can be the potential guys for different spots in future," Prasad said.
A squad of 26 will ensure that India can be divided into two groups and a warm-up game could be played during the quarantine period.
"Since we cannot trust the net bowlers about their exposure to COVID, it would be ideal to go with a large contingent as we can be assured of all the players' safety as they will be in a bio-secure environment," Prasad reasoned.
"In case someone tests COVID positive, then the players from this contingent can be picked as they would have served the mandatory quarantine period," he added.
Prasad opined that it will be a healthy preparation for the main team as the first-choice batsmen will have a wide variety of bowlers at their disposal.
"Even for our main bowlers, they will have fresh batsmen to bowl at unlike the same bunch of first team boys. For instance, Shreyas Iyer is very aggressive and at times can be unorthodox. So, he might offer variety of skills which the Australian batsman might posses.
"On the other hand, a left-armer Khaleel Ahmed's presence will help in preparing for Mitchell Starc's angled deliveries," said Prasad.
A good bunch of reserve fast bowlers would be ideal as the first team bowlers like Jasprit Bumrah, Mohammed Shami, Ishant Sharma and Umesh Yadav won't get tired in the nets in the absence of net bowlers.
The other reason to carry a big squad is that Sunil Joshi's panel will not have a reference frame as there would be no domestic cricket before the start of Ranji Trophy.
if there is no domestic cricket happening then taking a large group of players will help the final squad in terms of quality preparation leading up to the Test series, reckons Prasad.
"Also, if IPL is going to happen prior to this series then carrying a large contingent is better as we need to be ready with back ups in case somebody gets injured or is carrying the niggles from the IPL."
But there are a few disadvantages also and Prasad cited a couple of them.
"The only tough part that we will be facing because of this large contingent is managing such a large pool of players. To provide quality practise sessions to all of them will also be a challenge," said Prasad.
The other reason is that save for Cheteshwar Pujara and Hanuma Vihari (the two unsold Test players in IPL), others will have to switch from T20 to Test mode.
"If IPL is going to happen prior to this series then majority of these players would have played in it and then carrying extra players might become a debatable issue.
"But let's not forget that IPL is only a T20 tournament which may not be ideal preparation for Test series," said Prasad.
Asked to put on the selector's hat one more time, the former India wicketkeeper picked up his choice of 26 players -- a mix and match of Test, ODI and T20 specialists.
Openers: Rohit Sharma, Mayank Agarwal, Prithvi Shaw, KL Rahul.
Middle-order: Virat Kohli (captain), Ajinkya Rahane, Cheteshwar Pujara, Hanuma Vihari, Shubman Gill, Shreyas Iyer;
Wicketkeeper: Rishabh Pant, Wriddhiman Saha.
Spinners:Ravichandran Ashwin, Ravindra Jadeja, Shahbaz Nadeem, Rahul Chahar, Kuldeep Yadav,
All-rounder: Hardik Pandya
Pacers: Ishant Sharma, Mohammed Shami, Jasprit Bumrah, Bhuvneshwar Kumar, Umesh Yadav, Navdeep Saini, Khaleel Ahmedh, Shardul Thakur.
Purely white ball: Deepak Chahar, Yuzvendra Chahal, Krunal Pandya.