The 32-year-old left Manchester City after nine seasons to join the Hammers during the summer and has played in all four of the club's Premier League games this season.
The east Londoners were pointless before Monday's 2-0 home win over Huddersfield Town, with the Argentina star being given more scope to operate further up the pitch in a different position against the Terriers.
He put on an excellent display, both in attack and defence, and told the club's official website that it was vital for the rearguard to hold firm after their early-season troubles.
"I played as a wing-back against Huddersfield. It’s been a long time since I played in that position, but I was happy with the performance," he said.
"I always tried to support in attack and also always try to be in the right position defensively. Overall I think we were solid at the back.
"We needed a performance like that as defenders because in the last three games we conceded 10 goals. That wasn’t good enough, so I’m very happy with the performance overall. The whole team did great."