Gloucester need a win and other results to go their way if they are to qualify for the Guinness Premiership semi-finals after slipping to a 13-6 home defeat to Worcester on Tuesday.
It was win or bust for the Cherry and Whites as, after being right up there with the Premiership leaders most of the season, two significant league defeats dropped them to sixth place before kick-off.
One of those losses was away at Worcester on March 22.
And, although under-pressure Gloucester coach Dean Ryan had fresh legs to call on after his side's 50-12 EDF Energy Cup final hammering by Cardiff Blues on Saturday, defeat for them would mean a mountain to climb away to Wasps in five days time.
By half-time, the home side were struggling as captain Gareth Delve turned down three kickable penalties to go for touch and possible tries.
It was a high risk strategy which backfired in the opening 40 minutes. Gloucester pounded Worcester in the first 10 minutes, dominating possession and preventing the visitors from exiting their own side of the pitch.
But the points would not come. Reluctantly, Delve allowed former England centre Olly Barkley to boot a penalty from 20 metres that put Gloucester 3-0 ahead.
Worcester, against some tired bodies from that Twickenham disaster, held firm if not too spectacular and, when they had their chances to make inroads on Gloucester, they took them.
Full-back Willie Walker, on loan at Worcester from Gloucester, punished his own club with two penalties.
And just before the interval, Gloucester found themselves 10 points behind at 13-3 when lock Greg Rawlinson secured possession, passed to number eight Netani Talei and saw big Fijian outsprint home wing Mark Foster down the touchline to score unopposed.
It did not help either that Cherry and Whites hooker Scott Lawson was sin-binned for illegally kicking the ball away from an attacking Warriors ruck but, after the break, Worcester were also reduced to 13 men when flanker Tom Wood dipped his shoulder into full-back Olly Morgan.
Gloucester looked rudderless and in need of a leader to settle them down but, despite squeezing the life out of the visiting pack in the scrums, they just could not find someone to settle them down.
Barkley booted a second penalty as the attempt to get four tries bit the dust and all Gloucester wanted was the victory.
Italy international Marco Bortolami and Rawlinson found themselves the latest men in the sin-bin when they threw a couple of punches at each other.
And big flanker Apo Satala nearly grabbed a first home try on 68 minutes but was just hauled into touch two metres from the line before Barkley hit the post with a penalty wide out.
Gloucester threw the kitchen sink at valiant Worcester in the final quarter but the visitors, just as they did in the reverse fixture last month, held on to the bitter end and deserved the win.
Pens: Barkley 2
Pens: Walker 2
Gloucester: 15 Olly Morgan, 14 Matthew Watkins, 13 James Simpson-Daniel, 12 Olly Barkley, 11 Mark Foster, 10 Carlos Spencer, 9 Gareth Cooper, 8 Gareth Delve (capt), 7 Akapusi Qera, 6 Luke Narraway, 5 Alex Brown, 4 Adam Eustace, 3 Carlos Nieto, 2 Scott Lawson, 1 Alasdair Dickinson.
Replacements: 16 Olivier Azam, 17 Nick Wood, 18 Marco Bortolami, 19 Apo Satala, 20 Rory Lawson, 21 Henry Trinder, 22 Charlie Sharples.
Worcester: 15 Willie Walker, 14 Marcel Garvey, 13 Alex Grove, 12 Dale Rasmussen, 11 Rico Gear, 10 Matthew Jones, 9 Ryan Powell, 8 Netani Talei, 7 Pat Sanderson (c), 6 Tom Wood, 5 Graham Kitchener, 4 Greg Rawlinson, 3 Darren Morris, 2 Aleki Lutui, 1 Callum Black.
Replacements: 16 Shaun Ruwers, 17 Chris Fortey, 18 David Lyons, 19 James Collins, 20 Jonny Arr, 21 Loki Crichton, 22 Miles Benjamin.