West Ham manager David Moyes told BBC Sport: "We saw a poor West Ham in the first half but we also saw a good Brighton team in the first half. They made it difficult for us but the resilience of the players kept us going and a few changes helped us.
"We thought it was the right time to have a look at a back five again but I felt we didn't press them well enough. Lanzini has been an important player for us in recent years and I'm hoping to get him back to the levels he has been because he is a talented player and we needed that."
Brighton manager Graham Potter told BBC Sport: "Frustration is the emotion at the moment. We felt we did enough for three points but the second goal is the one that has punished us, and if you don't defend that situation better, you come away with just one point.
"Over the course of the game, I felt we did a lot well, particularity in the first half. It is hard to control 90 minutes of a Premier League game. You have to accept the opposition will step forward and show some momentum. After the goal, we felt more in control and to see it out better is the thing we have to improve on."