Baines was asked if he thought the defence was the weaker part of the unit after the latest loss, to which the left-back responded: "Not particularly.
"I don't think we have given up too many chances in the two games, but when we have, we have been punished.
"The tournament has been a bit like that. There have been a lot of goals so far and we'll have to look at it in the next couple of days."
The first goal in Sao Paulo was certainly preventable, with Edinson Cavani only able to lay on an exquisite chipped assist after being afforded space to find Suarez, who lost his man to head home.
A draw looked to be on the cards when Wayne Rooney levelled with 15 minutes remaining, only for Steven Gerrard to inadvertently head into the path of his Liverpool team-mate to finish the match.
"We got ourselves back in the game and got a bit of momentum going," Baines said.
"With that momentum it felt like we may have been able to go and win it ourselves but we were punished in the end. It is just disappointing.
"It was difficult. I thought we were probably the better team over the course of the whole game but we have been punished by good goals.
"Suarez is a top player. He didn't put himself about as much as he normally would but looked like he was always waiting for that moment, that opportunity to pounce, and he did.
"You are at the top level of the game and it is small margins - we haven't been outplayed in any of the games, we have just come up short maybe."