The Ospreys kicked off the Pro12 league with a comfortable win over last season's beaten finalists Leinster at Liberty Stadium.
Scrum-half Rhys Webb scored the early opening try as the hosts began with pace and purpose.
Wing Hanno Dirksen was next to cross and skipper Justin Tipuric went over at the end of the opening period.
Dan Biggar kicked the rest of the Ospreys' points, Mat Berquist replying with a penalty.
But there were no points scored in the second-half stalemate that denied the hosts a bonus point triumph.
The Ospreys did not have to wait long to make their mark in an opening period in which their rising talent's attacking potential came to the fore.
Lock Ian Evans won possession at an attacking Leinster ruck and Webb began the 60-metre counter-attack in which Biggar, Ashley Beck, Andrew Bishop and Beck again helped to send the scrum-half over within two minutes of the start.
Biggar converted and added a penalty before Dirksen was brought down short and Jonathan Thomas denied by the video referee.
However, South African-bred Dirksen was not to be denied at another attempt, diving low and early to beat the defence for a score awarded by the television official.
Fly-half Biggar added the extra points from the touchline to take his Ospreys' tally to 700 points.
Leinster's Berquist failed with his first penalty attempt and Biggar added a drop-goal before his opposite number put the visitors on the scoreboard.
But the Ospreys underlined their first-half dominance as skipper Tipuric showed his speed and athleticism to gather a kick ahead to score their third try.
Biggar again converted to give the hosts a 27-3 half-time lead.
However, having been on top throughout the opening period, the hosts reverted to past habits after the break.
Leinster - also full of young players in the absence of familiar World Cup players - showed greater cohesion with ball-in-hand allied to a more direct approach.
The pressure the Heineken Cup holders applied drew the Ospreys into a series of breakdown offences that tested the patience of referee Peter Fitzgibbon.
Eventually that patience wore so thin Tipuric was sent to the sin-bin.
Even so Leinster were unable to translate their numerical advantage into points as the Ospreys held firm in defence.
Victory for the hosts meant they have won all five of the home games that have started their seasons at this level.
For Leinster it was also a familiar tale as they remain without a win on their opening night of any cross-border league season since a solitary 2002 success.
Ospreys: Fussell; K Phillips, Bishop, Beck, Dirkson; Biggar, Webb; D. Jones, M Davies, Griffiths, Gough, Evans, Smith, Tipuric, Thomas.
Replacements: Isaacs for K Phillips (60), Parker for Beck (66), Morgan for Biggar (72), Rees for D Jones (63), Dwyer for M Davies (78), Dowding for Griffiths (76), Allan for Smith (60).
Not Used: King.
Yellow card: Tipuric (52)
Leinster: Nacewa; Carr, O'Malley, Fitzgerald, D Kearney; Berquist, Cooney; van der Merwe, Strauss, Hagan, Browne, Toner, McLaughlin, D Ryan, R Ruddock (capt).
Replacements: Madigan for Berquist (52), Willis for Cooney (41), O'Connell for van der Merwe (77), Dundon for Strauss (68), McGrath for Hagan (57), Flanagan for Browne (57), Auva'a for R Ruddock (62).
Ref: Peter Fitzgibbon (Ireland).