India’s Test squad was struck with another injury blow ahead of the gruelling cricket tour of Australia as pacer Varun Aaron was replaced by Vinay Kumar owing to a back problem. Aaron has become the second first-choice pacer after Praveen Kumar to be replaced from the squad due to injury.The 22-year-old Aaron has got “stress reaction on the back” which he sustained during the ongoing ODI series against the West Indies.Aaron was left out of the ODI team after playing the first two matches at Cuttack and Visakhapatnam.  The 27-year-old Vinay has not played any Test cricket so far.His nascent career is just 15-ODI old and the Karnataka bowler has taken 16 wickets so far. He has also played 5 Twenty20 matches picking up five wickets.