Bohemians produced their best defensive display of the season to book their place in the Setanta Sports Cup final at Windsor Park.
The Airtricity League champions will face St Patrick's Athletic, probably at Tallaght Stadium, in next month's final after Paddy Madden scored early on to put his side through.
Pat Fenlon had questioned his players' desire in the wake of their shock 3-2 defeat to Galway United on Friday, and the Gypsies manager made three changes to his line-up with Mark Rossiter, Jason McGuinness and Killian Brennan replacing Conor Powell, Owen Heary and the cup-tied Gareth McGlynn.
The Airtricity League champions have started sluggishly in most of their games so far this season, so the travelling fans would have been delighted to see their charges go in front after just five minutes.
Paul Keegan's ball over the top caught the Linfield back four flat and Paddy Madden took full advantage, racing on to the ball and holding off Steven Douglas to beat Alan Blayney from the penalty spot.
Linfield attempted to hit back immediately, but the Bohemians defence looked strong save for one jittery moment from Mark Rossiter whose mishit clearance fell to Paul Munster who failed to capitalise.
It was the away team who looked the more threatening on the break and after Douglas had made a poor attempted clearance, Brennan’s pinpoint cross found an unmarked Jason Byrne, but the striker’s header was straight at Blayney.
The Northern Ireland international was almost left red faced when a Madden cross dropped dangerously over the bar, while a minute later Raffaele Cretaro defied his small stature by rising highest to meet Rossiter’s cross only for Blayney to turn the header around the post.
Ken Oman headed wide from the resultant corner, but with the home fans on their back the Belfast side set about getting a goal and Munster had two shots blocked from a Billy Joe Burns long throw.
Damien Curran had two bites at a free kick after Oman had fouled Michael Gault, but the first was saved by Barry Murphy, and after Madden had broken from the wall and received a yellow card, the second flew over.
The Blues emerged after the break and battered at the Bohs door for 20 minutes, but they missed chance after chance to bring themselves back into the game.
Munster was the main culprit, but Madden made a crucial intervention in the goal he had scored in, heading Michael Gault's effort off the line, on to the bar and away.
Put through by Thompson, Munster fired wide moments after Murphy had saved well when Michael Carvill's shot came off the striker.
An unmarked Thompson headed straight at Murphy, before Munster and William Murphy fired wide. Fenlon brought Mark Quigley, Anto Murphy and Powell on to steady the ship and they saw Bohs home.
Linfield: 14 Alan Blayney; 2 Steven Douglas, 4 Michael Gault, 5 William Murphy, 14 Aaron Burns (17 Curtis Allen 69); 10 Michael Carvill (8 Philip Lowry 63), 12 BJ Burns, 20 Robert Garrett, 7 Damien Curran; 9 Peter Thompson, 23 Paul Munster.
Subs not used: Stuart Addis, Jim Erwin, Brian McCaul, Mark McAllister.
Yellow Cards: Douglas 74, Thompson 90)
Bohemians: 1 Barry Murphy; 4 Brian Shelley, 5 Jason McGuinness, 6 Ken Oman, 4 Mark Rossiter (3 Conor Powell 77); 9 Raffaele Cretaro (7 Anto Murphy 63), 8 Paul Keegan, 14 Glenn Cronin, 11 Killian Brennan; 12 Paddy Madden, 10 Jason Byrne (18 Mark Quigley 72).
Subs not used: Stephen Traynor, Gary Burke, Aaron Greene, Chris O'Connor.
Yellow Cards: Madden 39.