Stefano Pioli said Lazio deserve to be back in Europe's top-tier competition after his team qualified for the UEFA Champions League on Sunday.
Lazio pipped Napoli to third in a winner-takes-all season-ending Serie A clash via a 4-2 victory in Naples.
With the match level at 2-2 and both teams down to 10 men, Gonzalo Higuain had the chance to put Napoli ahead from the spot in the 76th minute.
But the Argentina international skied his penalty over the bar before Lazio substitutes Ogenyi Onazi and Miroslav Klose punished the hosts late in the game.
Sunday's victory saw Lazio finish third, six points clear of Napoli, who dropped to fifth in the standings.
"I always said my team was special, a side with high moral values," Pioli told Sport Mediaset.
"We did everything tonight to make life difficult for ourselves, but we do deserve to be in this position.
"The only regret this season is the Coppa Italia final defeat to Juventus. The team is perhaps not quite able to handle two big games in four days yet.
"We are only at the beginning. This year we laid the foundations for something important in the future."
Rafael Benitez, who is tipped to replace Carlo Ancelotti at Real Madrid, was hoping for the perfect farewell, however, Lazio had other ideas as goals from Marco Parolo and Antonio Candreva put the capital club 2-0 up at half-time.
Napoli regrouped in the second half, Higuain bagging a brace either side of Parolo's red card for two bookable offences in the 62nd minute.
And while Napoli's Faouzi Ghoulam saw red with 20 minutes remaining, Benitez's men were offered a route to the Champions League when Senad Lulic fouled Christian Maggio inside the penalty area five minutes later.
Higuain missed the resulting penalty though – his fourth failed attempt of the season - as Lazio denied Napoli a place in UEFA's premier competition, with two goals in the final five minutes.
Pioli added: "Napoli had a great opportunity, but there was still time for us to draw level even if he had scored. Our third place is deserved.
"We've already started to talk about the transfer strategy and made a few suggestions. The club shares my ideas. We want to improve the squad, as next season will be complicated."
