Rangers were hoping to book a place in the fifth round for the first time since Trevor Sinclair scored his famous bicycle kick goal against Barnsley in 1997 and had the better of the opening exchanges.

Pompey goalkeeper Craig MacGillivray was called into action for the first time when Darnell Furlong flicked a header into his arms after ghosting in at the near post to meet Freeman's corner.

It took until the 28th minute for Steve McClaren's side to create their first meaningful chance.

Freeman floated in a free-kick from the left and Lynch found himself unmarked only to head tamely into the gloves of a grateful MacGillivray from eight yards.

Pompey captain Brett Pitman did have the ball in the net moments later but the goal was ruled out after referee Gavin Ward spotted a foul on Rangers defender Toni Leistner.

The south coast side almost took the lead on the brink of half-time when Louis Dennis' dipping 20-yard volley was acrobatically tipped over the crossbar by Joe Lumley.

Pompey, who beat Championship promotion contenders Norwich in round three, created another great chance four minutes after the restart.

The busy Dennis floated the ball over the top of the Rangers defence but could only lift his shot over the crossbar with just a helpless Lumley to beat.

The home crowd exploded in joy when Kenny Jackett's men took the lead in fortuitous fashion three minutes past the hour mark.

Republic of Ireland winger Ronan Curtis rolled the ball forward for the overlapping Brown down the left and his cross was turned into his own net by the hapless Lynch.

Rangers hit back when Wells found the roof of the net to claim his seventh goal of the season and despite an open conclusion to the game, neither side could find a winner.

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