Scarlets kept the pressure on the top four in the Magners League thanks to a workmanlike 22-16 victory over Treviso at Parc y Scarlets on Sunday.
But they will rue missing out on the four-try win as they now sit five points behind three of the teams in the top four.
Jonathan Edwards, Tavis Knoyle and Jonathan Davies scored the tries for the home side, but it wasn't enough to gain a potentially vital extra point.
Despite the Scarlets starting with the intent to garner that potentially crucial bonus-point victory, they lacked accuracy and Treviso fly-half Kris Burton punished that with an early penalty.
Welsh fly-half Stephen Jones responded four minutes later to level matters and then converted an Edwards try after he took advantage of a disorganised defence from the Italian side.
Burton reduced the deficit with another three points before the move of the match saw the Scarlets extend their lead. Morgan Stoddart darted into a gap and then passed to Gareth Maule who drew the defence to release Rhys Priestland who then shifted it on to substitute Knoyle to go over for a converted try.
It was 17-6 at half-time and that was increased six minutes in the second period when centre Davies collected winger George North's intelligent off-load. Jones couldn't add the extras from the touchline and then Burton booted his third penalty to give the away team a glimmer of hope.
Their mood was further boosted by the sin-binning of Scarlets flanker Edwards but they couldn't take advantage, and when Ezio Galon was also yellow carded, it was 14 against 14. But Tobias Botes touched down to give the Italian side a losing bonus-point.
Tries: Edwards, Knoyle, Davies
Con: Jones 2
Scarlets: 15 Rhys Priestland, 14 George North, 13 Gareth Maule, 12 Jon Davies, 11 Morgan Stoddart, 10 Stephen Jones (capt), 9 Gareth Davies, 8 Ben Morgan. 7 Johnathan Edwards, 6 Rob McCusker, 5 Aaron Shingler, 4 Lou Reed, 3 Rhys Thomas, 2 Rhys Lawrence, 1 Iestyn Thomas.
Replacements: 16 Emyr Phillips, 17 Rhodri Jones, 18 Peter Edwards, 19 Damian Welch, 20 Josh Turnbull, 21 Tavis Knoyle, 22 Regan King, 23 Scott Williams.
Treviso: 15 Joseph Maddock, 14 Ludovico Nitoglia, 13 Andrea Pratichetti, 12 Gonzalo Garcia, 11 Michele Sepe, 10 Kristopher Burton, 9 Fabio Semenzato, 8 Robert Barbieri, 7 Alessandro Zanni, 6 Benjamin Vermaak, 5 Corniel Van Zyl, 4 Valerio Bernaḅ, 3 Ignacio Fernandez Rouyet, 2 Leonardo Ghiraldini (capt) 1 Michele Rizzo.
Replacements: 16 Diego Vidal, 17 Matteo Muccignat, 18 Lorenzo Cittadini, 19 Gonzalo Padṛ, 20 Paul Derbyshire, 21 Simon Picone, 22 Tobias Botes, 23 Luke McLean
Referee: John Lacey (IRFU)