At last, a point on the road for Barnsley. And a deserved one after a spirited second-half showing.
O’Brien’s timely goal also ended a run of six successive away defeats for the Reds and makes it three games unbeaten now for the rejuvenated South Yorkshire outfit.
A mistake from skipper Martin Cranie looked to have cost his side dear after he failed to pick up Murphy from a corner and the striker headed powerfully inside the right-hand upright.
But O’Brien pounced with 20 minutes remaining for his first goal since February to make sure of a point.
Reds boss David Flitcroft named an unchanged side to that which drew 1-1 at home to South Yorkshire rivals Sheffield Wednesday last Saturday.
And that was because midfielder Paddy McCourt passed a late fitness test, having torn a buttock muscle. He had been rated a major doubt earlier in the week, needing a painkilling injection to play against the Owls.
McCourt has been one of the Reds’ better performers this season and his inclusion was a boost for the visitors as they looked to end a run of six defeats in a row on the road.
Meanwhile, Mick McCarthy - who celebrated his 12-month exactly to the day of taking charge at Portman Road - named an unchanged side for the seventh games in succession as his side looked to end a run of four games without a win.
And it was the hosts who had the better of the first half chances after a steady 20 minutes where both sides failed to threaten.
In fact, the only talking point of the opening exchanges was when Chris O’Grady cut Ipswich defender Tommy Smith just above his right eye with a leading elbow.
Thankfully the chances came and Smith headed over soon after when, ironically, O’Grady miscued a clearance into his own box.
A minute later Paul Anderson volleyed over the bar with a fine right-fooed strike after David McGoldrick had chested the ball into his path.
Cranie gave the ball away, got back to chase Aaron Creswell, but the winger’s left-wing cross deflected off the defender and Reds keeper Jack Butland had to make a smart block at his near post.
Leading scorer McGoldrick blazed high and wide with an ambitious effort from an acute angle as the home team continued to press for an opener. Then Cresswell rifled a cross-cum-shot across the face of goal after a darting run down the left-hand side.
Luke Chambers headed over from an Anderson corner as Ipswich continued to dominate, before the deadlock was finally broken.
With Jacob Mellis temporarily off the pitch with an ankle injury, the Reds were down to ten men and McCarthy’s side took full advantage.
Cranie lost Murphy and the forward powered a header into the bottom-right corner four minutes before the break.
On the stroke of half-time Anderson shot straight at Butland, and three minutes after the interval Murphy forced the Stoke City loan keeper into action at his near post.
O’Grady had a shot brilliantly saved by Ipswich keeper Dean Gerken just after as the Reds came within a whisker of equalizing.
O’Brien powered over from distance less then a minute later as the visitors started to play with more freedom.
Norway international Marcus Pedersen shot over in the 68th minute, before two minutes later O’Brien pounced for the equaliser.
McCourt’s whipped-in cross from the left was flicked on by Smith and O’Brien coolly slotted into the bottom-left corner.
Sub Jason Scotland had two good chances to win it for the Reds late on against his former club, but he had a goalbound shot blocked and then rifled into the side netting.
Former Reds loanee Frank Nouble had a penalty appeal turned down in injury time after a challenge from Jean-Yves M’voto. Aaron Cresswell was sent off after the final whistle for complaining about the decision.
Ipswich: Gerken, Cresswell, Chambers, Smith, Berra, Skuse, Murphy, McGoldrick (Nouble 82), Anderson (Tabb 69), Tunnicliffe (Taylor 82), Hyam. Subs: Leach, Hewitt, Edwards, Mings.
Barnsley: Butland, Kennedy, Cranie, O’Grady, Perkins, Wiseman, Pedersen (Scotland 74), Mellis (O’Brien 43), M’voto, Fox, McCourt (Etuhu 81). Subs: Dibble, Hassell, Cywka, Jennings.
Goals: Murphy 43 (Ipswich); O’Brien 70 (Barnsley).
referee: Andy D’Urso