"Now, I feel like crying because we worked so hard, suffered so much, we deserved this joy," the 26-year-old told DAZN.
Inter Milan's Scudetto is easily Inzaghi's biggest honour since winning it as a player with Lazio 24 years ago, and comes after three years of off-field turbulence and serious financial problems which he has navigated with aplomb.
Goals from Francesco Acerbi and Marcus Thuram gave Inter a 17-point advantage over closest challengers Milan and secured their 20th league crown with five matches of the season remaining.
Noah Okafor salvaged a hard-fought point for Milan in the 84th minute on a hot spring day in Reggio Emilia, but second-placed Milan still risk conceding the Scudetto to Inter in a hotly-anticipated derby despite coming back from two goals down.
Italy midfielder Frattesi poked home the decisive goal in the fifth minute of stoppage time in Udine to maintain Inter's 14-point lead at the top of the table with seven matches left in the season.
Monday's comfortable victory left Inter needing just 11 more points from eight matches to beat second-placed AC Milan to a 20th Italian league crown.
Italian club Napoli said they were "stunned" after Italy's football federation (FIGC) on Tuesday dropped a probe into alleged racist comments made by Inter Milan's Francesco Acerbi to Napoli's Juan Jesus due to lack of evidence.
Francesco Acerbi on Monday left Italy's training camp ahead of two friendlies in the United States after reports he will be investigated for alleged racial abuse of Napoli defender Juan Jesus.
Juan Jesus nodded home Napoli's leveller with nine minutes remaining after fighting back from Matteo Darmian's opener shortly before half-time to snatch a deserved point.
Cristiano Ronaldo was replaced at half-time as Al Nassr drew 1-1 with Champions League finalists Inter Milan in the second game of their pre-season tour in Japan on Thursday.
Juan Cuadrado has signed for Inter Milan, the Serie A club announced on Wednesday as fans protested the arrival of the Colombia winger after being released by bitter rivals Juventus.
Manchester United are closing in on the signing of Inter Milan goalkeeper Andre Onana for a fee of £47 million ($61 million, 55 million euros), multiple UK media outlets reported on Tuesday.
Former Barcelona and Inter Milan midfielder Luis Suarez the only male footballer born in Spain to win the Ballon D'Or died at the age of 88 on Sunday.
Brozovic, 30, joined Inter in 2015 and helped them win Serie A in the 2020-21 season followed by two Italian Cup trophies.
The 37-year-old, who played in Inter's Champions League final defeat by Manchester City earlier this month, has signed a two-year deal with the Istanbul-based club.
Roberto Mancini's side take on Spain in Enschede, the Netherlands on Thursday.
Thierry Henry said that it will be difficult for Romelu Lukaku to handle after he made some crucial mistakes in Inter's Champions League final loss against Manchester City.
"We do have regrets because defeat is the worst thing in sport but I have to congratulate my lads," Inzaghi said after the final was decided by a solitary second-half goal from Rodri
It shouldn't come as a massive surprise if the Piacenza-born tactician lands the biggest prize of all in Istanbul on Saturday night, even though Manchester City will definitely go into the game as the favourites.