In their opening FIFA World Cup encounter against the tournament debutants on Sunday, Argentina - and Messi in particular - looked disjointed for large parts of the game.
Having taken a third-minute lead through Sead Kolasinac's own goal, Argentina struggled to build on their early advantage.
That was until the 65th minute when Messi exchanged passes with substitute Gonzalo Higuain, beat two men and curled a low shot in off the left-hand upright to double his side's advantage, with Vedad Ibisevic's late goal no more than a consolation for Bosnia.
Sabella, who conceded that Argentina have room for improvement, was quick to praise his captain and talisman.
"On balance I would give it (Argentina's display) a six (out of 10)," he said.
"We need to improve and part of that is in my hands - it is up to me.
"The changes at half-time (which saw Higuain and Fernando Gago enter the fray to prompt a change in formation) just produced this improvement. They were playing better together and there was more support around Messi.
"Once Messi received the ball there was better follow-up and better support.
"I think that, whatever happens in this World Cup, he is among the best players in the history of football."
