The line of this Marshall opening is so well-analyzed, yet GMs come with subtle variations.
In all fairness, Svidler could have easily held a draw and was doing pretty well. He made some really gross inaccuracies, presumable under time pressure and allowing the knight on f5 on move 37 was the final blow.
Well done Vishy!
However, 9 rounds to go and lots of chess still to be played.