Mark Roberts scored a penalty in the third minute of injury time as Partick Thistle secured a dramatic 2-2 draw against Inverness to maintain their Tennent's Scottish Cup dream.

The Firhill striker had opened the scoring in the 44th minute when he diverted a Scott McCulloch free-kick into the net.

But Roy McBain equalised in the 59th minute with a rising drive from 12 yards out.

Craig Dargo then headed Caley into the lead after connecting with a McBain cross.

But Roberts was to have the last word after being brought down himself inside the area by Ross Tokely to earn the Bell's Second Division side a replay.

A robust Partick side signalled their intentions to turn the match into a physical encounter and forced four Caley players to receive medical attention within the opening 45 minutes.

First, combative Caley midfielder Ian Black came off second best in a challenge with Billy Gibson.

And, despite trying to run off the affects of an ankle knock, the former Blackburn player had to be replaced by Stuart Golabek in the 19th minute.

Grant Munro picked up a foot injury after a late challenge from Marc Smyth, before the Thistle defender clattered into the back of Dargo resulting in a head knock for the striker.

Caley captain Darren Dods suffered a gash above his right eye in an aerial challenge.

And, after being patched up, he played the remainder of the match sporting a sizeable bandage around his forehead.

The home side had offered little in the opening half, with a first-minute Barry Wilson shot, which spun just wide via a deflection from Sandy Hodge, the closest they came to scoring.

However, Inverness were made to pay for their profligacy in the final minute of the first half when Roberts stooped to divert a powerful free-kick from McCulloch past the stranded Mark Brown.

Caley boss Charlie Christie was forced into a defensive reshuffle at the interval with Munro replaced by Liam Fox.

But Caley responded well to the loss of their central defender and equalised 13 minutes into the second half.

Tokely's low cross bobbled across the Partick penalty area and, when it fell to McBain, he lashed the ball high into Kenny Arthur's net from 12 yards out.

That strike clearly lifted the home side and, 12 minutes later, Inverness came agonisingly close to taking the lead when Wilson's audacious 30 yard volley struck Arthur's post.

In-form striker Dargo then looked to have sent Inverness into the quarter-finals when his sixth goal in five games doubled the home side's advantage.

However, after Arthur produced a fantastic block to deny substitute Fox a goal eight minutes from time, Tokely bundled Roberts to the ground in the box.

The striker stepped up to confidently score the resultant penalty kick in a dramatic conclusion to the match.

Teams:

Inverness CT Brown, Tokely, Dods, Munro (Fox 45), Hastings,Wilson, Duncan, Black (Golabek 19), McBain, Dargo,Wyness (Bayne 78).

Subs Not Used: Fraser, Proctor.

Booked: Hastings.

Goals: McBain 59, Dargo 77.

Partick Arthur, Murray, Smyth, Hodge, McCulloch (Boyd 74),Gillies (Dodds 83), Billy Gibson, James Gibson, Strachan,Ritchie, Roberts.

Subs Not Used: Colin Stewart, Craig, Brady.

Booked: James Gibson, Smyth.

Goals: Roberts 45, 90 pen.

Att: 3,286

Ref: C Murray (Scotland).