The Barcelona coach's normally lethal strike force, boasting Champions League top scorer Lionel Messi and former Inter striker Zlatan Ibrahimovic, were blunted by Jose Mourinho's tireless troops, even after they were reduced to 10 with more than an hour of the semi-final second leg remaining.
It was left to central defender Gerard Pique, thrown forward as an extra striker as the clock ticked down, to give Barca hope with a superb 84th-minute strike, but with the home fans baying for a second goal that would send their heroes through Inter held firm.
NEWS:Ten-man Inter reach Madrid final
GALLERY:Barca 1-0 Inter
Guardiola had started with only three regular defenders and although his players had a whopping 76 percent of the possession, with Xavi and Sergio Busquets dominating the midfield, they managed only four shots on target.
Inter trio Esteban Cambiasso, Cristian Chivu and Wesley Sneijder ran their socks off in midfield and Lucio and Walter Samuel were rocks in central defence, repelling wave after wave of Barca assaults.
Guardiola said Inter midfielder Thiago Motta's 28th-minute red card had disrupted the flow of the play and helped throw the holders off their stride.
"The sending off shaped the game because they just sat back and attacking is always much harder than defending," the 39-year-old former Barca player said.
"We were missing some continuity in our game," he added. "We had a lot of possession but didn't manage to create many chances and there was little space between the defence and the middle of the pitch.
"When there are nine players defending in the area it's not easy. We tried but they defended very well and that's it."
ARCH RIVALS
After last season's unprecedented treble of Champions League and domestic league and cup, Barca's only chance of silverware this campaign is in La Liga.
They lead by a point from arch rivals Real Madrid with four matches remaining and face a potentially tricky match at in-form Villarreal on Saturday as well as a trip to Sevilla.
"We have to have a talk among ourselves, pick ourselves up and face the challenge in front of us," Guardiola said.
"The only thing we can do is congratulate Inter and wish them well for the final," he added. "Then tomorrow we have to begin preparing for the remaining four league games."
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