Lazio's 11-match winning run in Serie A was ended on Sunday following a 1-1 derby draw with AS Roma that was decided by two goalkeeping errors.
Thomas Strakosha misjudged a cross to allow Roma's Edin Dzeko to head in the opener after 26 minutes, but Lazio were level just eight minutes later when Pau Lopez failed to gather his own punch before Francesco Acerbi tapped in.
Roma came closest to clinching the win when Lorenzo Pellegrini curled a shot off the post, but Simone Inzaghi's side held on to stretch their unbeaten league run to 15 games.
Lazio are on 46 points, two behind second-placed Inter Milan and with a game in hand, while Roma have 39 points, one ahead of Atalanta.
"I'm proud of how my players did, we played very well against an excellent team," Roma coach Paulo Fonseca told Sky Sport Italia.
"If we look at the statistics, it's incredible that we didn't win. We tried to attack constantly and by playing like this, it's easier to believe in this team. I think the lads deserved more than the result they got today."
Roma were awarded a penalty in the second half when Justin Kluivert went down in the box, but the decision was overturned after a pitchside review by referee Gianpaolo Calvarese.
Strakosha then atoned for his earlier error with two good saves on Dzeko efforts, while a rasping effort from Lazio midfielder Sergej Milinkovic-Savic flew narrowly wide late on.
Lazio were relieved to hear the final whistle blow after mustering just three shots to Roma's 16, and having just 33% possession.
"Technically we got many things wrong and Roma prepared an intense match," admitted Lazio coach Inzaghi.
"We could have done better and I was expecting more. Now we need to recover our energy, hoping that nobody else picks up knocks, because we have 18 finals ahead of us."