Rodriguez Vicente's double earned victory for Brighton, who moved into the Championship play-off places, while Portsmouth remain bottom of the table.
Brighton dominated the second half and defender Joe Mattock crashed a half-volley against the post from six yards.
And with 15 minutes left, Vicente fired home a low free-kick from 20 yards to give the hosts a deserved lead.
The Spaniard doubled their advantage in injury time, firing home from 10 yards following Kazenga LuaLua's pass.
The result sees Brighton, who are unbeaten in 12 games, move up to fifth in the table while beleaguered Portsmouth are now eight points from safety.
The visitors, who were last month deducted 10 points for going into administration, were the first to have an opening but Luke Varney curled narrowly wide of the right-hand post from 25 yards.
Scott Allan then made some room for himself just outside the area before his rasping drive was tipped around the post by Seagulls goalkeeper Peter Brezovan.
On the stroke of half-time, the hosts nearly took the lead as an almighty scramble in Portsmouth's penalty box - created by Alan Navarro's long-range shot - ended with Sam Vokes being denied by Jamie Ashdown from close range.
After the break Mattock's volley struck the post before Pompey cleared their lines to ensure the score remained goalless.
Seagulls manager Gus Poyet then introduced former Spain international Vicente for Noone in an effort to break the deadlock. And the replacement almost had an immediate impact as, after Ashley Barnes's strike was blocked by Tal Ben Haim, Vicente's follow-up was saved by Ashdown.
The 30-year-old was not to be denied though, and his free-kick following David Norris's foul put Brighton well on their way to three points.
Portsmouth did push forward in an attempt to force an equaliser but their failure to test Brezovan was telling and their misery was compounded in injury time. LuaLua picked out Vicente from the left and he made no mistake from close range, although there was a clear handball in the lead-up to the goal.
Brighton & Hove Albion
- 01 Brezovan
- 02 Mattock
- 03 Greer
- 06 El-Abd
- 36 Jara
- 08 Navarro
- 11 Noone (Vicente - 58' )
- 26 Bridcutt
- 30 Buckley (LuaLua - 79' )
- 09 Barnes
- 24 Vokes (Mackail-Smith - 69' )
- 16 Ankergren
- 14 Calderon
- 15 Vicente
- 25 LuaLua
- 12 Mackail-Smith
- 01 Ashdown
- 02 Ward
- 03 Rocha
- 05 Pearce
- 15 Halford Booked
- 26 Ben-Haim Booked
- 16 Allan
- 19 Norris (Kitson - 85' )
- 20 Thorne
- 09 Futacs (Maguire - 79' )
- 11 Varney
- 31 Webster
- 04 Mokoena
- 14 Etuhu
- 18 Kitson
- 22 Maguire
Live Text Commentary
Full Time The referee blows for the end of the match.90:00 +3:21
The assist for the goal came from Kazenga LuaLua.90:00 +3:21 Goal scored
Goal! - Rodriguez Vicente - Brighton 2 - 0 Portsmouth Rodriguez Vicente grabs a goal from close in low into the middle of the goal. Brighton 2-0 Portsmouth.90:00 +1:20
Craig Mackail-Smith challenges Tal Ben-Haim unfairly and gives away a free kick. Tal Ben-Haim crosses the ball from the free kick right-footed from right channel, clearance by Gordon Greer.90:00 +1:03
Unfair challenge on Scott Allan by Adam El-Abd results in a free kick. The free kick is delivered right-footed by Scott Allan from right channel.84:53 Substitution
Substitution Dave Kitson replaces David Norris.81:47
Chris Maguire concedes a free kick for a foul on Joe Mattock. Free kick taken by Joe Mattock.80:43
Corner taken by Kazenga LuaLua, clearance by Chris Maguire.78:24
Direct free kick taken by Jamie Ashdown.78:24 Substitution
Substitution Will Buckley leaves the field to be replaced by Kazenga LuaLua.78:24 Substitution
Substitution (Portsmouth) makes a substitution, with Chris Maguire coming on for Marko Futacs.78:24
Unfair challenge on Tal Ben-Haim by Ashley Barnes results in a free kick.77:44
Will Buckley takes a inswinging corner to the near post.76:47
Free kick awarded for a foul by Ricardo Rocha on Ashley Barnes. Rodriguez Vicente delivers the ball from the free kick left-footed from right channel.74:52 Goal scored
Goal! - Rodriguez Vicente - Brighton 1 - 0 Portsmouth Rodriguez Vicente scores a goal direct from the free kick from outside the area to the bottom left corner of the goal. Brighton 1-0 Portsmouth.74:00
David Norris gives away a free kick for an unfair challenge on Rodriguez Vicente.73:26
Ricardo Rocha concedes a free kick for a foul on Craig Mackail-Smith. Direct free kick taken by Joe Mattock.70:32
Ashley Barnes takes a shot.68:54 Substitution
Substitution Craig Mackail-Smith joins the action as a substitute, replacing Sam Vokes.67:53
Rodriguez Vicente takes a shot. Save made by Jamie Ashdown.
Outswinging corner taken right-footed by Scott Allan from the right by-line.63:49
Corner taken by Rodriguez Vicente.60:31
Joel Ward takes a shot.58:27
Free kick awarded for a foul by David Norris on Ashley Barnes. Peter Brezovan takes the free kick.56:45
Jamie Ashdown takes the direct free kick.56:45 Substitution
Substitution Rodriguez Vicente is brought on as a substitute for Craig Noone.56:45
Foul by Sam Vokes on Greg Halford, free kick awarded.56:27
Corner from left by-line taken by Craig Noone.56:04
Joe Mattock produces a right-footed shot from deep inside the area which goes wide of the left-hand post.55:16
Foul by Tal Ben-Haim on Craig Noone, free kick awarded. Craig Noone takes the direct free kick.54:38
Unfair challenge on Scott Allan by Alan Navarro results in a free kick. Tal Ben-Haim crosses the ball from the free kick right-footed from right channel, Gordon Greer makes a clearance.45:01
The referee starts the second half.45:00 +2:14 Half time
Half Time The ref blows to end the first period.45:00 +1:13
Alan Navarro takes a shot. Sam Vokes takes a shot from 6 yards. Clearance made by Ricardo Rocha.44:53
George Thorne gives away a free kick for an unfair challenge on Ashley Barnes. Liam Bridcutt restarts play with the free kick.40:29
Inswinging corner taken left-footed by Craig Noone from the right by-line, save made by Jamie Ashdown.39:59
Marko Futacs is adjudged to have handled the ball. Free kick taken by Alan Navarro.39:26
Shot from just outside the area by Scott Allan goes over the bar.38:35
Gonzalo Jara Reyes takes the free kick.38:35 Booking
Booking The referee shows Tal Ben-Haim a yellow card for unsporting behaviour.38:30
Tal Ben-Haim is penalised for handball and concedes a free kick.37:43
Inswinging corner taken by Scott Allan from the left by-line played to the near post, clearance by Adam El-Abd.34:13
Effort on goal by Scott Allan from long distance goes harmlessly over the target.31:14
Corner from the right by-line taken by Scott Allan, clearance made by Sam Vokes.30:05
Free kick awarded for an unfair challenge on Joe Mattock by Marko Futacs. Joe Mattock takes the direct free kick.26:54
Adam El-Abd gives away a free kick for an unfair challenge on Marko Futacs. Free kick taken by Tal Ben-Haim.24:06
Inswinging corner taken from the left by-line by Scott Allan.22:55
Inswinging corner taken by Craig Noone, save by Jamie Ashdown.19:27
Corner taken short by Scott Allan.18:26
George Thorne has shot on goal from just outside the box which goes wide of the right-hand upright.17:19
The assistant referee signals for offside against Sam Vokes. Jamie Ashdown takes the indirect free kick.16:08
Will Buckley takes the inswinging corner, clearance made by Jason Pearce.14:43
Corner taken short by Will Buckley.14:09
Shot from outside the penalty box by Luke Varney goes wide right of the goal.12:25
Craig Noone fouled by Greg Halford, the ref awards a free kick. Free kick crossed by Liam Bridcutt.10:38
Free kick crossed by Liam Bridcutt.10:38 Booking
Booking Greg Halford receives a caution for unsporting behaviour.10:31
Greg Halford gives away a free kick for an unfair challenge on Craig Noone.10:05
Foul by Joel Ward on Ashley Barnes, free kick awarded. Free kick taken by Liam Bridcutt.8:48
Outswinging corner taken by Will Buckley.4:52
Craig Noone challenges George Thorne unfairly and gives away a free kick. Greg Halford takes the direct free kick.0:32
Craig Noone concedes a free kick for a foul on Scott Allan. Greg Halford restarts play with the free kick.0:00
The ref blows the whistle to begin the match.
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