Barcelona's Lionel Messi reacts during the UEFA Champions League match against Borussia Monchengladbach at Camp Nou stadium in Barcelona, Spain, Dec 6, 2016. Barcelona won 4-0. [Photo/Xinhua]

The five-time Ballon d'Or winner was a persistent threat throughout the first half, but Barca captain Andres Iniesta also impressed in his first start for six weeks following a knee injury.

Only Gladbach goalkeeper Yann Sommer prevented Messi from adding to his tally before halftime.

However, it was Turkey international Turan who took center stage after the interval as he responded to criticism for committing the foul that led to Sergio Ramos' equalizer for Madrid on Saturday.

"One moment doesn't decide a game," Enrique said in defense of the midfielder.

"We are not focused on that, and no matter what happens, players always need to score goals."

Turan was perfectly placed to head Denis Suarez's deflected cross home at the back post before producing a fine low finish into the far corner from Aleix Vidal's cutback.

Paco Alcacer's search for a first goal since his $32 million move from Valencia to Barca goes on.

The 23-year-old still made a contribution - crossing low as Turan completed his treble with a powerful finish that was too strong for Sommer to keep out.

Agence France-Presse