Lopetegui and his Hammers side are preparing to take on Fulham on Saturday.
The Spaniard spoke about having his full group to work with after the international break.
He stated: “Unfortunately for us, a lot of the players were away with their countries during the international break, so it’s not easy to work on things, but we’ve tried to take advantage of the time we have had with the players who have been here.
“We’ve worked on a lot of different things, and now we’re back as a full group.
“We’ve been waiting for the last few guys to come back, so we’ll have to evaluate everyone - physically and mentally - and see where we’re at before the game on Saturday.”
On their transfer business, he added: “The market is closed now, and we did the best we could to improve the squad all over the pitch.
“Some players left us, but we’ve brought in some great talent, and now we’re fully focused on the group we’ve got to help us going forward into the season.
“We want one strong team, with a collective feeling on and off the pitch. We’re not worried about one signing, or two signings, we’re concentrating on working together with one philosophy.”
On taking on Fulham, he finished: “It’s going to be a difficult match, for sure. They are a very balanced team, and they have had the same coach (Marco Silva) for a number of years now.
“They have a clear style, with great players, and of course they did well against West Ham last season.
“We are focused on being ready for the game though, and it will be difficult for them too. I’m really looking forward to it.”