Wales warmed up for their Euro 2008 qualifying campaign with a lively goalless draw in front of 8,000 fans at the Liberty Stadium in Swansea.
Wales midfielder Simon Davies was prominent in attack
Ryan Giggs had a first-half free kick clawed away by Bulgarian keeper Georgi Petkov, but Dimitar Berbatov caused havoc against Wales' 4-4-2 line-up.
The home side switched to 3-5-2 in the second half but still conceded chances.
But Rob Earnshaw, Craig Bellamy and David Vaughan all went close to grabbing a win for John Toshack's side.
Wales skipper Giggs' superb 11th-minute set piece from the edge of the area was followed by a Bellamy chance.
The Liverpool front man failed to finish after combining intelligently with Earnshaw, as chances opened up at either end.
Slack work from Wales' experienced defenders Mark Delaney and Danny Gabbidon gave opportunities to Berbatov and Stilian Petrov, James Collins then Paul Jones scrambling to deny them.
Earnshaw beat Stanislav Angelov only to see his goal-bound shot cleared, before Carl Robinson hit a weak strike after excellent build-up play from Giggs and Simon Davies.
Tottenham's £10.9m summer signing Berbatov - a constant source of trouble to centre-backs Gabbidon and Collins - set up Martin Petrov for the final effort of the half, but the Atletico Madrid man blazed over with a left-footed shot.
Wales felt hard done by early in the second period as Davies freed Earnshaw with a sweet through-ball, leaving the Norwich striker a clear run on Bulgaria's goal.
Keeper Dimitar Ivankov - a half-time substitute - charged out to pull down Earnshaw's chip, though his save appeared to be made outside the box.
Berbatov went close with a toe-poke then a header, prompting Toshack to ring the changes.
Joe Ledley replaced Carl Fletcher and Lewin Nyatanga came on for Giggs as Toshack switched to the 3-5-2 formation he is likely to use against the Czech Republic in the 2 September Euro 2008 opener in Teplice.
Ledley tried his luck with a left-footed volley, before the inexperienced Nyatanga cost his side a dangerous free-kick near the corner flag.
Duffy impressed as a second-half substitute
The ball was whipped across the face of the goal, a desperate Collins clearance sparing Nyatanga's blushes.
Richard Duffy replaced Delaney as Wales' unsettled backline spilled more chances to Angelov and Berbatov, though Bellamy's pace providing some relief up front for the home side.
Vaughan, Paul Parry and Rob Edwards replaced Sam Ricketts, Bellamy and Gabbidon, as Toshack preserved his squad for the long season to come.
Davies saw a dipping shot tipped over the bar by Ivankov, before the impressive Duffy set up perhaps the best chance of the game.
His pin-point cross found Vaughan clear in the area, but the Crewe man directed his header wide.
Wales: Jones, Delaney (Duffy 60), Gabbidon (Edwards 73), Collins, Ricketts (Vaughan 68), Robinson, Fletcher (Ledley 51), Davies, Giggs (Nyatanga 51), Bellamy (Parry 71), Earnshaw.
Subs Not Used: Brown, Cotterill.
Bulgaria: Petkov (Ivankov 46), Kishinev (Y Todorov 75), Kirilov, Tomasic, Wagner, Anglov (Iliev 81), Berbatov, Peev (Georgiev 56), Iankovic (S Todorov 63), M Petrov (Lazarov 56), S Petov.
Subs Not Used: Dimitrov, Svetoslav Todorov.
Referee: Joacquim Attard (Malta).