The Spanish champions defeated Shakhtar Donetsk 1-0 in the second-leg of their quarter-final tie in Ukraine on Tuesday evening to go through 6-1 on aggregate.
Guardiola took over the coaching responsibilities of Barca at the start of the 2008-09 season and won Europe’s premier club competition with the team that campaign.
Barca reached the last four of the Champions League last season too but failed to get past the challenge of Italian outfit Inter.
This time, the defending Spanish champions will confront arch-rivals Real Madrid for a place in the final should Jose Mourinho’s men progress from their tie against Tottenham.
“It is a gift to be in the Champions League [semi-finals] for the third consecutive season,” enthused Guardiola after the match to Spanish sports daily AS.
“These guys [the players] are incredible, not only this year but for three straight years.
“In the match, at first we struggled a bit but then we started to dominate the game. We knew that it would be difficult, and at first it was tough and we had to endure in the first few minutes.”
Barcelona’s next match is against Madrid in the Primera Division on Saturday evening. They are eight points clear of their rivals at the top of the table.