Chelsea retain FA Cup to seal double
Didier Drogba got the winner with a 59th minute free-kick after they hit the woodwork five times in the first half and Frank Lampard missed a late penalty.
In an astonishing match of twists and turns, Kevin-Prince Boateng, who scored from the spot in the semi-final at Wembley, also saw his 56th minute penalty saved.
The triumph gave the west London side a second straight FA Cup final victory, after they beat Everton last season, and their third success in four seasons.
Although the newly-crowned Premier League champions dominated relegated Portsmouth in the opening half, they were thwarted on five occasions when Drogba (twice), Frank Lampard, Salomon Kalou and John Terry all hit the bar or post.
Despite that Portsmouth's incredibly vociferous fans made the greater noise inside the sun-drenched stadium and stayed to applaud their side even after defeat.
Chelsea manager Carlo Ancelotti, who has won the Double in his first season in England, told reporters afterwards: "Its a fantastic victory for me, I am very happy.
"We won't do anything special to celebrate, I will follow my players and my friends. Wine, sure, champagne. It is right to have a celebration, the team had a fantastic season."
"It has never happened in my career to hit the bar or post five times in one half... and we didn't start too well in the second half but I was not worried because we were in control of the game and had chances to score."
Portsmouth manager Avram Grant said: "It was a very difficult season. It is a season I will not forget. I have won a lot of games in my life, trophies and everything, but this was unbelievable. We always played against the odds."
Chelsea began as 5-1 on favourites to beat Portsmouth who are in administration, have debts of 138 million pounds and finished bottom of the Premier League.
Some pundits had predicted a record FA Cup final victory following Chelsea's 8-0 trouncing of Wigan Athletic when they clinched the league title at Stamford Bridge last Sunday.
But Portsmouth, many of whose players might have been playing their last match for the club because of the financial problems and relegation, weathered the storm.
In contrast Chelsea had just one first half scare with Cech producing an outstanding reflex save to deny Frederic Piquionne.
Pompey's first close shave came after 14 minutes when Lampard shot against the outside of David James's left-hand post with a 25-metre drive.
Kalou was guilty of one of the most blatant misses in any Cup final after 27 minutes when he shinned an Ashley Cole cross against the bar in front of an open goal from four metres.
A minute later Chelsea captain Terry headed the ball against the bar again with the under-fire James beaten.
Portsmouth rode their luck once more 10 minutes later when James pushed Drogba's 30-metre free kick against the bar.
The right-hand post came to Portsmouth's rescue again two minutes later when Drogba cracked the ball against it from close range with England goalkeeper James again beaten.
The Ivory Coast striker, who will lead his country at the World Cup finals, showed his utter frustration by smacking the post with his hand.
Chelsea had four other chances in the opening period but they needed a stunning reflex save from Cech to keep out an instinctive close-range effort from Piquionne after 22 minutes.
The match finally turned Chelsea's way when Boateng's weak penalty, awarded after substitute Juliano Belletti brought down Aruna Dindane, was saved by Petr Cech's legs.
With that let off, Chelsea finally seemed to kick back into first gear, and Drogba fired home a 25-yard free-kick just three minutes later to maintain his record of scoring in all six competitive matches he has played for Chelsea at Wembley - including in three FA Cup finals in the past four seasons.
VIDEO: Watch Drogba's FA Cup winner
The striker, who will also lead Ivory Coast as captain in the World Cup, scored the winner in their 1-0 FA Cup final victory over Manchester United in 2007; Chelsea's only goal in a 2-1 defeat by Tottenham Hotspur in the 2008 League Cup final and the winner in the 2-1 semi-final victory over Arsenal in 2009.
Drogba also grabbed the equaliser in a 2-1 win over Everton in last season's FA Cup final and got the opener in Chelsea's 3-0 FA Cup semi-final win against Aston Villa last month.
Lampard fired wide from the spot in the 88th minute after a Michael Brown had clattered into him but Chelsea had already done enough to become the seventh club in English history to win the Double, the 11th time the feat has been achieved.
RECORD FOR COLE
Victory for Chelsea saw England defender Ashley Cole become the first player to collect six FA Cup winners' medals.
Cole won his first winners' medal playing for Arsenal against Chelsea in 2002 and won further medals with Arsenal in 2003 and 2005. He has also now completed three wins with Chelsea after also featuring in the winning sides of 2007 and 2009.
The 29-year-old had shared a record five FA Cup winners' medals with Arthur Kinnaird (The Wanderers and Old Etonians), Charles Wollaston (The Wanderers) and Jimmy Forrest (Blackburn Rovers), who all achieved the feat in the 19th century.
Meanwhile, Cole and team-mate Nicolas Anelka have also become the first players to win the English League and FA Cup Double with two different clubs.
Chelsea fans will look ahead with optimism to a new era of success under the stewardship of Carlo Ancelotti, who in steering the Blues to a domestic double in his first season has already made more of an instant impact at Stamford Bridge than Jose Mourinho. For Portsmouth the future is less certain.