The pattern of play was turned on its head at the start of the second half as, after Owen Farrell's penalty, Nick Abendanon capped a fine Clermont move with the try of the match to cut the gap to one point.
Saracens retained the European Champions Cup - and completed the first half of their quest for a second successive double - after a 28-17 victory over Clermont Auvernge at Murrayfield.
But the English champions clung on to the continental title they lifted for the first time past year when Alex Goode dived over in the corner seven minutes from time.
However, Sarries have suffered a setback in the build-up to the match with wing Sean Maitland - who has enjoyed a hugely impressive first season with the club - being ruled out for the rest of the campaign after picking up an ankle ligament injury against Wasps last weekend.
Farrell kicked Saracens further ahead with a penalty but Clermont struck back instantly. Clermont have fantastic players and their back-row are unbelievable over the ball; they seem to have heavy men all around the field.
Parra added the conversion and a penalty on the one hour mark.
It's relentless. As a winger, I felt a lot of the time that I was under pressure. A break by Brits carved an opening for prop Vincent Koch - if it had been Ashton on his shoulder it would have been another try - and Clermont were mightily relieved not to concede a penalty try when Camille Lopez knocked on Wyles's pass to Ashton with the line at his mercy. On 15 minutes Saracens drove a lineout, Goode grubbered the ball behind the French defence and it sat up perfectly for Ashton to score.
Farrell and Morgan Parra exchanged penalties to ensure the game entered the final quarter with only a point in it, with the holders next to threaten when Billy Vunipola was thwarted just shy of the line.
Armed inmate killed, hostage rescued at hospital
During entry, a SWAT officer fired their weapon, striking Salters, who was pronounced dead at the scene. He had been held at the jail on charges of possession of a stolen motor vehicle, police said.
Saracens centre Brad Barritt said: "We'd have taken a win no matter what".
"It's not a nice feeling to be the first to lose all three finals - we've just got to hope that next year's going to be our year".
The victory made Saracens the fourth team to retain Europe's premier club title after Leicester, Leinster and Toulon while perennial bridesmaids Clermont, who have lost 11 of their 12 French championship finals, became the first to play in three finals and lose them all.
"The pleasing thing was it felt and looked like we improved from a year ago".
England worldwide Billy Vunipola added: "It's such an incredible group of guys".
"We have the players who are capable of making sure we go on to win the Top 14 title, but that is going to be down to us mentally".
After Owen Farrell edged Sarries eight points clear, a dazzling Nick Abendanon try saw Clermont edge within a point. Man of the match was the power-running Billy Vunipola but it was a pure team effort from Saracens, every one of them a vital part of the superbly drilled machine that simply wears down the opposition. They've got some risky outside backs, they play with a lot of width and win lots of turnovers. "We still have a lot of work to do before I feel comfortable saying we're a great team".