La Viola rotated and nearly paid a heavy price early on, with ex-Manchester United forward Bebe firing wide from inside the six-yard box.
Vincenzo Montella's men dominated possession in the second half but were unable to force a breakthrough, thanks to some stubborn resistance from the hosts.
Look back on a frustrating night for Fiorentina's fringe forwards with Sports Mole's minute-by-minute text commentary below.
8.00pmEvening European football fans. Thanks for sticking with Sports Mole as we turn our attention to tonight's late games in the Europa League, with our focus here on Fiorentina's bid to maintain a 100% start on the continent against Portuguese outfit Pacos de Ferreira.
8.02pmTEAM NEWS! There is just about time to bring you news of wholesale changes for La Viola, which in unsurprising with qualification secured. Josip Ilicis is a rare starter for Vincenzo Montella's side, but has a chance to impress this evening. A full look at both teams will follow in just a moment.
8.03pmPACOS: Antonio Filipe; Tony, Tiago Valente, Ricardo, Helder Lopes; Anunciaçao, Andre Leao; Manuel José, Seri, Bebé, Ruben Ribeiro
0 minStraight into the action from Portugal then, with Fiorentina getting us underway shooting from right to left in changed all-white strip.
2 minFormer Manchester United winger Bebe quickly commits a foul on Bakic, with Fiorentina looking to settle in possession in the opposition half.
4 minAn assured start on the ball from the visitors, with Ryder Matos dropping deep to retain possession. Fernandez also looks lively in a withdrawn midfield role early on, with Pacos happy to sit deep and play on the break.
7 minPacos look tentative but are quick to close down Ambrosini and Aquilani in quick succession, with Ilicic then flagged for offside as he chases a long diagonal pass after cutting inside, but failed to time his run correctly.
10 minThe hosts win a corner kick but fail to make the set-piece opportunity count, as Manuel Jose's cross is knocked clear at the near post. More encouraging signs for the hosts though, after a fairly sloppy start.
13 minRibeiro flashes well wide from range, with Fiorentina happy to let that effort sail well wide of the target. La Viola then begin to build from the back once again, content to probe patiently for now.
16 minPacos waste another corner kick, with Bebe picking up the pieces to fire wide from just outside the penalty area. Fiorentina's play has lacked urgency so far tonight, which with qualification secured may not be a huge surprise.
18 minBebe clips Ilicic to concede his second foul of the night, perhaps a sign that the Pacos forward should refrain from attempting to win the ball back in those areas. Fiorentina pick up play and look for Fernandez on a long diagonal pass, but the Chilean just fails to keep the ball in play at the byline.
21 minMISS! Bebe has just spurned a glorious opportunity to give Pacos the lead, firing straight to the goalkeeper when it seemed easier to turn home from inside the six-yard box. The hosts got the benefit of a dubious offside call in the build-up to that effort, but may well end up ruing what was a glaring error from their bulky frontman.
24 minYELLOW CARD! Bakic goes into the referee's notebook after hacking over Helder Lopes with a late lunge. The midfielder protests but the official's patience has worn thin after a first 20 minutes littered with cheap fouls.
27 minCompper is the latest offender to commit a fairly cynical foul, pushing Seri to the floor around 30 yards from goal. From the following free kick Manuel Jose sends a dangerous cross towards the near post, but despite a promising flick-on the visitors eventually clear comfortably.
30 minA wild swing across goal from Ilicic ends a promising Fiorentina counter and ends up trickling out for a throw-in, the best they have mustered since the opening passage of play. This match is lacking a moment of star quality at this stage.
33 minPacos manage to string together a succession of neat passes without threatening a strike on goal, before Bakic is penalised for a foul on Ricardo thanks to a trailing leg. He really needs to be careful after being cautioned early on.
36 minIlicic has attempts to cut inside blocked by Helder, with Fiorentia forced to settle for a corner kick. Fernandez quickly sees his corner cleared but Ambrosini picks up the pieces and wins a free kick just outside the penalty area, chopped down by Filipe after just winning a footrace for possession.
39 minFernandez can only send a tame free kick into the wall as La Viola win another corner kick, which Ilicic swings high towards the far post. Pacos quickly smash clear and find Bebe on the break, who cuts inside before electing to turn and keep possession with little support.
42 minFiorentina nearly force a mistake from Pacos goalkeeper Filipe, who rushes off his line with no chance of claiming a long diagonal pass. Luckily for the hosts Valente read the danger, dropping deep to control and hack clear into touch.
45 minAquilani is this time guilty of a blatant shove on Seri in midfield, once again forcing a break in play as Pacos are awarded a free kick. That should just about do it for the first 45 minutes.
8.58pmA fairly even first half draws to a close with Pacos having every right to feel they should be ahead. Bebe was presented with absolute sitter but somehow contrived to miss from inside the six-yard box with time to pick his spot. Fiorentina have shaded possession but offered little in the way of an attacking threat.
9.01pmYou sense that Fiorentina will get a rollocking from Montella at the break, despite qualification being secured. La Viola have lacked their usual pace and zip in possession, while Ilicic has been given little service to work with in a rare start in attack.
9.04pmThere is just time before the second half begins to inform you that Dnipro lead Pandurri in tonight's other Group E clash, which means that La Viola will stay top of the section by only a point as it stands heading into the final match against the Ukrainian side. Maybe that score will provide the visitors with some extra incentive to improve when play resumes.
45 minSUBSTITUTION: We are back underway with news of a change in midfield for Fiorentina, with Pizarro replacing Bakic to remove the risk of a second yellow card.
48 minFernandez threatens to get on the end of a looping diagonal pass as Fiorentina press the action, but Marcos Alonso is unable to keep the ball alive after losing out near the corner flag. There was a bit more urgency about the way the visitors flooded forward from that fleeting attack.
51 minMatos is flagged for offside after just staying too far forward in an effort to meet Aquilani's quick pass, rendering his smash towards goal irrelevant. Fernandez then quickly has the visitors back in possession, controlling neaty in midfield under pressure.
54 minCompper comes across to stop Bebe driving down the wing, with Pacos settling for a corner kick after Tony slipped over but still saw his miscue take a deflection. Manuel Jose's cross from the set piece is a major disappointment though, easily swept clear by the visitors.
57 minJose has another chance to whip in a corner kick but again fails to find a yellow short in the box, as Roncaglia rises highest to clear. Pizarro then feeds Aquilani to lead a Fiorentina break, which ends with Pizarro settling for a free kick after being pushed off the ball by Ribeiro.
60 minYELLOW CARD! Bebe's night is over and it's been one he'd quickly like to forget in truth, with the forward replaced by Hurtado as Pacos add fresh legs in an advanced wide position.
63 minAquilani makes a break beyond the strikers for the first time tonight and is very nearly rewarded, controlling a long pass before smashing over on the half-volley. Fiorentina need runners from midfield more often if they want to force a late winner.
66 minSUBSTITUTION: Montella decides to make an attacking change and clearly still wants to win this match, with Juan Cuadrado replacing Ambrosini. The Colombian should bring natural width, pace and most importantly crosses for Ilicic and Matos.
70 minWIDE! Ruben curls a swerving strike well wide of the target after Pacos had done well to rob Pizarro of possession deep in opposition territory. Fiorentina then quickly advance up the other end and picks out Fernandez in the penalty area, but he falls to the ground under minimal contact from Valente. Pizarro wanted a spot kick and is swiftly booked for taking his protests too far.
73 minAquilani is rather harshly penalised for a foul on Seri as the match threatens to peter out. Pacos decide to make a change before taking the free kick, with Ruben replaced by Oliveira.
76 minA final change for La Viola as Ilicic is swapped for Yakovenko, after a fairly anonymous display. Time is running out for the visitors to cement their spot at the top of Group E.
79 minCuadrado offers width for the first time tonight after linking up with Roncaglia out wide, who has a teasing cross headed clear at the near post. From the following corner Fernandez picks out Aquilani, who has a downward header comfortably held by Filipe.
82 minYELLOW CARD! Valente is cautioned for a desperate challenge on Fernandez just outside the penalty area, but Fiorentina are unable to take advantage from the free kick as Aquilani hits a low effort into the wall. They get another opportunity from the following corner, with Compper's effort blocked at the near post. That's about as close as the visitors have come to a breakthrough tonight.
85 minFiorentina keeper Munua is given something to think about late on, forced to tip over Olivieira's effort on the half-volley from 12 yards. Pacos send plenty of bodies forward for the corner kick, but cannot make it count as La Viola clear comfortably.
88 minThis game is starting to open up late on as Matos blasts over after choosing to take on a volley first-time. Play is then help up with Pacos keeper Filipe down injured and requiring treatment.
90 min+2Filipe gets back to his feet and quickly has to make what may well prove to be an important stop, parrying Cuadrado's fierce effort that looked to be flying inside the top corner.
9.58pmA frustrating night for Fiorentina then, who now still have work to do in a bid to secure top spot in Group E. That just about brings an end to our live text coverage from the Europa League this evening, but be sure to stick with Sports Mole for comprehensive reaction from a busy night of action across the continent. Good evening!