Small, sparrow-sized black bird in Al Qudra old lake

Hazy shot of a small black passerine bird in Al Qudra Lake on 30 January 2019

Yesterday was Dubai Safari Conservation team's field survey day. We landed in old Al Qudra Lake by later afternoon. It was little windy but sunny. As we passed a feeding area birds got scattered. From the car we saw a completely black-sparrow sized bird perched on an Acacia tree fully laden with yellow flowers. By the time I could position my camera the bird started flying and my colleague could only get these two shots of no quality for identifying any bird.

Only clue I had was that it was a pure black bird and did not resemble redstarts at a first glance because it kept its body upright and was with the sparrows.

Could any one of you guess, or id it? Nearly impossible though.

However, could it be a Black Redstart and that in a hurry we missed the important features!

Thanks for your kind efforts.