The Barcelona superstar was virtually anonymous in the first 45 minutes but turned on the style after the break, capping an improved performance with a superb goal
Sead Kolasinac inadvertently turned a Messi free kick into his own net after just three minutes to break the Bosnian resistance, but much of Argentina's performance for the opening 45 minutes was uninspired.
Messi was particularly notable for his lack of influence, and at halftime Sabella introduced Fernando Gago and Gonzalo Higuain in place of Hugo Campagnaro and Maxi Rodriguez to give his team more attacking options, while switching to a more conventional 4-3-3.
The Barcelona superstar responded with a much-improved display after the break and scored one of the goals of the tournament so far to claim the man of the match award. Sabella admitted that his changes at the interval were designed to help Messi get into the game.
"During the first half we controlled the Bosnian team, but beyond that and handling the ball we needed more depth and that’s what we achieved in the second half," he told reporters.
"As soon as we brought in Higuain [Messi and Aguero] had more company and we were able to put together the game that has characterized Argentina for a long time.
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"We brought in two things: Better provisioning and once Messi received the ball, better follow-up and better support.
"Messi is the best player in the world. It is not that he needs a lot. Beyond that there’s always a context and it can empower him a bit more. In this case the support - he received a push from his colleagues which empowered him."
Sergio Aguero sparked injury fears when he appeared to limp off the field on 87 minutes, but Sabella insists he has no long-term concerns over Manchester City star's fitness.
"I saw he was tired," the Argentina coach added. "There was very little time to play and I wanted to make the substitution before that when it was 2-0.
"We needed a fresh player and I was between introducing another attacking player or a defensive one, but I took him out because he was tired."
Sabella also reiterated his belief that Messi does not need to win a World Cup to cement his legacy in the game.
"Messi is the best player in the world beyond what happens in this World Cup and he is among the best players of all time, beyond what happens in this World Cup," he insisted.