Dundee United stretched their unbeaten run to five games with a dull draw against St Mirren in Paisley, where midfielder John Rankin saw red late on.
A drab first half was brightened by some silky wing play from Gary Teale.
In the second period it was more open, with Dougie Imrie's half-volley for Saints and Craig Samson's save from Michael Gardyne the highlights.
Rankin was sent off for a two-footed tackle on John McGinn with a couple of minutes left.
With a week to go before St Mirren have their day at Hampden for the Scottish Communities League Cup Final, excitement is building.
However, that fervour has been tempered by recent league form being the wrong side of average, underlined by a disappointing defeat to bottom club Dundee midweek.
A win against Dundee Utd here was vital to keep alive any faint hopes of a top six finish.
But therein lies the problem, because Saints have not beaten United at home since 2001. Ironically, St Mirren icon Steven Thompson scored for the visitors that day.
The main oohs and ahhhs in this contest early on were in response to two heavy challenges from the hosts.
Referee John Beaton's yellow cards were given an early airing to both Conor Newton and Graham Carey after bringing down Richie Ryan and Gary Mackay-Steven respectively.
Mackay-Steven's Scotland call-up put him under the spotlight more than usual, but St Mirren had their own tricky, blonde winger in Teale, and he whipped in an inviting ball which Thompson narrowly failed to get his head to as the first half reached it's midway point.
What Scottish football has learned about St Mirren's Esmael Goncalves is that when he plays, he normally scores. He almost did again on 32 minutes when Ryan's misplaced pass was collected and sent goalward by the Portuguese striker.
The second-half began with the visitors showing more attacking threat as Armstrong drove a 20-yarder over and Rory Boulding fired wide on the turn.
Saints' sub Jon Robertson, on for Newton, shot high from Paul McGowan's lay-off to further convince the crowd it might be a more open half.
Goncalves then benefited from a snaking run by McGowan to curl side-footed straight into Cierzniak's arms.
As the game moved into its last 20 minutes, there was no doubt United's most impressive player of the afternoon was Armstrong. He was involved again in setting up Barry Douglas and Gardyne, the latter's chance curling just wide with Samson rooted to the spot.
St Mirren's Imrie was next to draw a gasp from the crowd, his half-volley narrowly missing the bar after coming on for Thompson.
Samson was on hand to rescue Saints on 80 minutes, saving brilliantly point-blank from Gardyne following a scramble at a United corner.
Then, with minutes remaining, the game got a red card instead of a goal.
It was Rankin's two-footed crunching tackle on McGinn which saw referee Beaton take action.
The Tangerines go five games unbeaten while St Mirren's point means Dundee failed to make up more ground on them at the bottom.