The touring side, ranked number one in the world, defeated Sri Lanka by 304 runs inside four days to take a 1-0 lead in the three-match series.
While Shikhar Dhawan put India in the driver's seat on the opening day with a sparkling 190 off just 168 deliveries, it was his opening partner Abhinav Mukund's turn to shine in the second innings with an 81.
Dhawan only came into the squad as a replacement for the injured Vijay, while Rahul was forced to miss the first Test due to a viral fever.
"Yes, it's a very tricky situation," Kohli told reporters.
"(And) we've got a fourth guy who's a regular opener for India who's not fit (Vijay). We've got all four openers firing now.
"Shikhar was supposed to go (home) to Melbourne, now he's got a 190 in Galle. So, anything can happen in life."
Kohli said he hoped whoever missed out would understand.
"It's a massive headache but I guess a good one. You know, eventually guys understand that only two can take the field and at most two or three openers make the squad," the 28-year-old told reporters.
"It's going to be tough but it's something that any day you'd like to be in this situation rather than having guys that are not scoring."