Northampton Saints opened their latest bid for Heineken Cup glory with a laboured 18-14 victory over Pool 1 rivals Castres at Franklin's Gardens on Friday night.
Castres stunned the home fans with a try from Joe Tekori midway through the first half and although Bruce Reihana hit back for the Saints, it was the visitors who led at the break thanks to a drop goal from fly-half Cameron McIntyre.
Ben Foden's try right at the start of the second half swung the game back in Northampton's favour but they failed to build on that score and only managed to see the game out thanks to a penalty apiece from Geraghty and his replacement Stephen Myler as Castres escaped from Franklin's Gardens with a valuable losing bonus point.
Northampton, quarter-finalists last season, began brightly against their French opponents, who are tenth in the Top 14. Indeed, within two minutes of the start, Saints had obtained a foothold in the Castres 22 following a powerful burst from Courtney Lawes and some elusive running from England hopeful Geraghty.
Reihana had the first chance to open the scoring after 10 minutes but his long-range penalty attempt was hit well wide. Once again the combination of Geraghty and Lawes ripped the French defence apart but somehow the visitors kept their line intact.
After 17 minutes Reihana was presented with another penalty opportunity but his kick went badly astray. Moments later Castres had their chance but fullback Pierre Bernard failed with an optimistic penalty attempt from inside his own half.
On a couple of occasions in the opening quarter Castres looked lively in attack but it was a shock and against the run of the play when they took the lead after 21 minutes. They moved the ball swiftly along the line with neat play from Bernard and flanker Ibrahim Diarra which culminated in Tekori driving over from close range for the try which was confirmed by the video referee. Bernard's conversion attempt fell narrowly wide.
Stunned by the reverse, back came the Saints and they were awarded another penalty. This one was much easier, but Reihana made another hash of his kick from an angled 22 metres. With nine minutes to go before the interval Northampton finally got on the scoreboard. Castres lost a lineout in their own 22, allowing the home forwards to drive for the line and when the ball came back a clever blindside pass from Lee Dickson sent Reihana over totally unopposed in the corner. The wing missed his fourth kick with a difficult touchline attempt.
McIntyre restored the French lead with a neat drop goal but this success was immediately offset by the loss of hooker Matthieu Bonello to the sin-bin. With the last kick of the half, Geraghty's penalty attempt to level the scores almost ran across the floor.
Within 40 seconds of the restart the hosts were ahead. Geraghty ran to the blindside from a ruck 35 metres out. He fed Phil Dowson, whose splendid inside pass sent fullback Foden on a clear run to the line for a try which Geraghty converted.
Bernard then had a chance to cut Northampton's lead but his 55-metre kick was nowhere near. Despite this reverse, it was Castres who dominated the third quarter and Bernard's penalty after 60 minutes was just reward for this effort
Two minutes later the visitors were penalised and Geraghty restored his side's four-point advantage. Bernard had another penalty chance but his decent effort fell short before the visitors' fullback set up a tense finale with a successful kick with 10 minutes to go.
At long last Northampton raised their game and put the French under pressure. The visitors offended and Myler knocked over the penalty with three minutes to go, allowing the Saints to claim a crucial win.