Domenico Berardi says Italy gave their all but admitted they needed to find even more after their failure to qualify for the World Cup.
The Azzurri's hopes of reaching Qatar ended following a shock play-off semi-final defeat by North Macedonia on Thursday, with Aleksandar Trajkovski striking a stoppage-time winner in Palermo.
No player registered more shots at the Renzo Barbera stadium than Berardi (eight), but just two of those were on target.
And the Sassuolo forward was made to rue his profligacy as the hosts suffered a first-ever World Cup qualifying loss on home soil.
Roberto Mancini's side claimed glory at the European Championship just eight months ago, after beating England on penalties in the final.
But for the first time in their history, they will be absent from consecutive World Cups, having also missed out in Russia four years ago.
Over 48 hours on, Berardi revealed the pain of missing out on the finals is still raw, but he is determined to put things right.
Addressing his 278,000 followers on Instagram, he posted: "A cool head hurts even more. The dream for all of us Italians ended in the worst way.
"Believe it or not, we've really done a lot. We tried in every way, but it wasn't enough.
"It was the goal of the whole group to go to the World Cup. For many of us, [it would have been] the first time to play the most beautiful cup for our country.
"It was our responsibility to take you to the World Cup and live a wonderful adventure all together like the one last summer.
"We had to and could have given more because what angers us most is that we are not there. There aren't many things to add. We will work to make you dream again. Together. United. Azzurri."