Troy Parrott scored twice but the Republic of Ireland were forced to settle for a 2-2 draw after Austria came back in the second half of their Nations League encounter at the Aviva Stadium in Dublin.
The contest was twice interrupted in the opening 45 minutes, first due to what campaign group Stop the Game later referred to in a statement as a "limited tennis ball protest", when - around the 20th minute - tennis balls wrapped in stickers featuring the Palestinian flag and the text '#StopTheGame' were launched on the pitch.
The match paused a second time when an invader entered the pitch and was promptly tackled and carried off by security.
Parrott scored a sensational 12th-minute opener and added a penalty on the stroke of half-time.
A pair of substitutes proved Ireland's undoing after Alexander Prass halved the deficit in the 71st minute and Michael Gregoritsch drew the sides level six minutes later.
Heimir Hallgrimsson's men had a chance to top Group B3 with a victory, but they sit third behind Austria and Kosovo at the halfway point of the group stage.
Hallgrimsson made three changes, including the reintroduction of Finn Azaz, who was greeted warmly when his name was announced over the PA system before the match.
Goalkeeper Gavin Bazunu, who had made himself unavailable for the Israel meetings, was back in the squad, while Liam Scales and John Egan were awarded starts.
There was a significant security and police presence outside the stadium, where a small group of protesters also gathered before kick-off.
There was an audacious early effort from Sasa Kalajdzic, who tried to catch Caoimhín Kelleher off his line with a lob from midfield, before Ireland enjoyed a couple of attacking spells deep in the visitors' half.
It was a brilliant opener from Parrott, who realised he was on his own after bringing down Adam Idah's glanced-on header from a goal kick.
The Real Betis striker was sandwiched in a triangle of white shirts, before nutmegging Philipp Lienhardt and evading every other challenger with a mazy run before planting the ball past Florian Wiegele and into the bottom corner.
Play was briefly paused just before the 20th minute to clear up the tennis balls, a pause both teams used for a water break.
The second stoppage of play took place around the 35th minute, when a man ran on to the field of play from the opposite side, carrying what appeared to be a Palestine flag.
Kelleher denied Patrick Wimmer and there were a few more promising spells for Austria before Parrott doubled their lead.
Ryan Manning won the penalty after he was clipped in the box by Nicolas Seiwald. Parrott stepped up after a VAR check and blasted it past the Austria 'keeper.
Austria cut the deficit after Liam Kitching was caught out and Austria worked the ball to the unmarked Prass, who blasted the ball beyond Kelleher. The offside flag was initially raised, but the decision was reversed after a VAR check.
The Brentford goalkeeper then failed to stop Gregoritsch, guessing the wrong way as the Augsburg forward fired into the corner.
Ireland captain Dara O'Shea was denied by an excellent leaping Wiegele save, Gregoritsch directed a shot over the crossbar, and both sides fended off attempts at a late winner.