Edinburgh's Scott Murray (right) is tackled by Tomas Tierney
Connacht 22 (10)
Pens: McHugh 5.
Edinburgh 22 (16)
Pens: Paterson 4, Hodge.
Mark McHugh's injury-time penalty earned Connacht a share of the spoils in Friday's Magners League clash at the Sportsground in Galway.
Chris Paterson scored all Edinburgh's first-half points, including a try, as they led 16-10 at the break, Matt Mostyn touching down for Connacht.
Five sin-binnings affected the flow of the game after the break as McHugh's penalties helped Connacht fight back.
Duncan Hodge's penalty edged Edinburgh ahead again before McHugh's late reply.
Some overzealous refereeing from Welshman James Jones turned the final 20 minutes into a lottery.
He sin-binned five players - three from Edinburgh and two Connacht - in the closing half hour as his no-nonsense attitude ruined a game in which there was little malice.
Two early penalties from Paterson sandwiched an eighth-minute try from Connacht winger Mostyn, who did well to collect a powerful pass from McHugh after an initial fumble.
Connacht's 7-6 lead lasted more than 20 minutes as the visitors struggled to turn their territorial dominance into points before Paterson grabbed a 10-point salvo just before the break.
The Scottish winger kicked his third penalty and then weaved his way in under the posts for a converted try.
McHugh landed a Connacht penalty in first-half injury-time before he swapped further penalties with Paterson just after the interval.
Referee Jones produced his first yellow card on 54 minutes when Connacht lock David Gannon walked for a ruck offence.
Amid farcical scenes, Gunners trio Alasdair Dickinson, Ross Rennie and Scott Murray all followed suit as did the home side's Matt Lacey.
The visitors were whittled down to 12 players at one stage, allowing Connacht to capitalise.
McHugh booted over two penalties to a single effort from replacement Duncan Hodge.
Connacht looked to have missed the boat when five phases of flowing rugby failed to net them the winning try.
However, they got the next best thing when the Gunners were penalised for not releasing in the tackle and the nerveless McHugh walloped over from 47 metres.
Connacht: D Riordan; M Mostyn, John Hearty, G Williams, K Matthews; M McHugh, C Keane; B Wilkinson, J Fogarty, B Sturgess; D Gannon, A Farley; J Muldoon, M Lacey, C Rigney. Replacements: A Flavin, M Diffley, M Swift, R Ofisa, T Tierney, D Slemen, D Yapp.
Edinburgh Gunners: H Southwell; C Paterson; B Cairns, R Dewey; S Webster, P Godman, M Blair, A Jacobsen, D Hall, A Dickinson, M Mustchin, S Murray, A Strokosch, A Hogg, R Rennie. Replacements: A Kelly, D Hewett, S Turnbull, D Callam, G Laidlaw, D Hodge, M Di Rollo.