For the third successive away game, Arnautovic found the back of the net for the Hammers, his latest strike coming 11 seconds into the second half at the John Smith's Stadium. Tom Ince fizzed a cross over from the left that Laurent Depoitre could not quite reach, then when Rajiv Van la Parra sent a ball in from a similar area it flew over Lolley's head.
The visitors went in front after 25 minutes following some tragic defending from the Terriers. Lossl passes to Lolley and puts him in trouble.
Making such a mistake on his first home Premier League start could have easily affected the 25-year-old, but he responded in the ideal fashion by levelling things up before the break.
Huddersfield have been well beaten here before, though only by teams from the top half of the table. A long ball from defence was flicked into the path of Austrian winger Arnautovic by Cheik Kouyate, before the former smashed the ball beyond Lossl to make it 2-1.
West Ham did make it 3-1 soon after as Lanzini raced clear and fired across goal into the bottom corner.
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New signings Alex Pritchard and Terence Kongolo were names on the bench by David Wagner.
West Ham were understandably delighted with the result and were equally impressed with the performance from Arnautovic during the game, taking to Twitter to provide their reactions.
- Marko Arnautovic had a hand in three goals in a single Premier League game for the first time in his career (one goal, two assists).
West Ham have creative individuals who today were able to hurt us.
Harry Kane scored twice for Tottenham as they crushed Everton 4-0 at Wembley.