Luis Alberto struck the only of the game on Saturday.
Ranieri lamented, “We were missing the final ball to send the players clear on goal. We provided a lot of smoke and not enough fire," Ranieri told Sky Sport Italia.
“I cannot ask for much more from the lads, we leave the field with our heads held high against an excellent Lazio side, and that is what's important for me. I think it was a very balanced game throughout, then Lazio broke the deadlock on our error, as we cleared it backwards rather than putting it out for a throw-in.
“In the final 10 minutes of the first half, we pushed hard and created quite a lot of pressure. I don't recall a Pepe Reina save, but it certainly wasn't a relaxed afternoon for Lazio. It's true they had a lot of counter-attacks, but they were almost all offside anyway. Perhaps the only one that wasn't saw Omar Colley intercept from Vedat Muriqi.
“We didn't make enough crosses to the near post, there was only one really that found Fabio Quagliarella, and I don't think it was a penalty. I didn't see it properly."