The Venezuelan striker was put through on goal against the run of play by Xisco Hernandez and his shot was blasted into the top corner giving goalkeeper Karanjit Singh no chance to make a save.
There was a question of offside but replays showed Miku had brought himself back onside before the pass was made that opened up Chennaiyin's defence.
"Yeah, it was a great goal - it's a part of my job," Miku said after the game. "In the end, I'm just happy because we started the league with a win. That was what was most important for us."
The Venezuelan was taken off very late in the game as Bengaluru looked to defend their 1-0 lead and the 33-year-old received a standing ovation from the Blues faithful.
"We know they are always in the stands for every game. We have great support here [at the Kanteerava] and they always believe in us. It's nothing new for us," he said with a smile.
Miku was the club's top goalscorer last season with 15 goals, ahead of club captain Sunil Chhetri who finished with 14 goals. He was only behind FC Goa's Ferran Corominas (18 goals) in the Golden Boot race for the 2017/18 season.
His form last season had even prompted two different Chinese Super League clubs to try and take the striker off Bengaluru FC's hands but the club refused to sell him after already having sold Spanish midfielder, Edu Garcia.
So does he have any personal targets for this season?
"No, I don't think about it in those terms," he said. "I only think about doing my job and winning games to become the champions.
"Of course, last year I scored a lot of goals but I was disappointed in the end because we lost the league title. I don't care who finishes as top scorer. I only care about winning the league."
Bengaluru's next game is also at home as they host the other new entrant from last season; Jamshedpur FC.