Fin Smith inspired Northampton Saints in a crushing nine-try win over an under-strength Bulls side to reach the Investec Champions Cup semi-finals.

The hosts took control after the break as Alex Coles, Ramm, Fraser Dingwall, Mitchell and Juarno Augustus scored.

Saints will face Leinster in the semis.

Bulls arrived at Franklin’s Gardens with 13 changes in personnel to the side that beat Lyon in the last 16 at Loftus Versfeld after citing travel disruption in the build-up.

Premiership leaders Northampton kept their foot on the accelerator to break the visitors’ resistance and reach their first Champions Cup semi-final since 2011.

Saints too slick for spirited Bulls

The only remaining South African side in the competition left several Springboks at home, including backs Willie le Roux, Kurt-Lee Arendse and Canan Moodie, and Saints showed their attacking ambition from the opening stages.

Smith fed Ramm for the opening try with a perfectly weighted flat pass, but the lead was short-lived as Hanekom powered his way over the line to spark the Bulls’ early resistance.

Saints’ response was instant as club stalwart Lawes, in his final season with the club, surged forward before having to roll close to the line and ground the ball behind him.

Television player of the match Sleightholme showed all of his power and nous to stretch Northampton’s lead as he looked for, and shrugged off, blue shirts to score the hosts’ third try.

England scrum-half Mitchell, on his return to the starting XV from a wrist injury, sniped over from close range, but the pendulum would swing again as first Van der Merwe caught the Saints short on the blindside and then De Klerk intercepted Mitchell’s pass to run the length of the field and turn defence into attack for the Bulls’ third try.

The depleted visitors returned to the sheds boosted by their part in a 50-point first half – a new high for a Champions Cup quarter-final.

But Saints returned to the field with real intent as a move off the training paddock saw Mitchell pop the ball to Lawes from the breakdown before one short pass the other way freed Tommy Freeman to play Coles in for a clear run to the line.

Ramm doubled his tally to stretch the lead before De Klerk crossed for the Bulls once more – only for it to be chalked off as Hanekom was penalised for tipping Dingwall beyond the horizontal in the lead-up to the try.

Smith, who also kicked 14 points, shone again for the seventh try as his slight movement kept the Bulls defence engaged before cleverly releasing the ball for Dingwall to cross, and Mitchell added the eighth with another smart finish from close range.

Augustus powered over for the ninth as Saints wrapped up an impressive victory to maintain their charge for a domestic and European double and set up a mouth-watering tie with four-time Champions Cup winner Leinster at Croke Park.

‘We put our foot down and accelerated’ – what they said

Speaking to BBC Radio 5 Live, Northampton director of rugby Phil Dowson said: “I’m delighted for the players, the club, the support staff and everyone involved. The way the playing group are doing, it is exciting and we are looking forward to that next challenge and we know how big it is.

“I thought we got a bit sloppy and went away from our fundamentals a little bit and were trying to force a few things, but at the start of the second half we put our foot down again and accelerated and played more like we are accustomed to.

“That [semi-final v Leinster] is going to be huge. We know Leinster have been one of the greatest sides in Europe over the last decade.”

Line-ups

Northampton: Ramm; Hendy, Freeman, Dingwall, Sleightholme; Smith, Mitchell; Iyogun, Langdon, Davison, Moon, Coles, Lawes (capt), Graham, Augustus.

Replacements: Matavesi, Waller, Hill, Mayanavanua, Scott-Young, Ludlam, James, Furbank.

Bulls: Williams; De Klerk, Immelman, Vorster, Jacobs; Smith, Burger; Matanzima, Van der Merwe, Smith, Swanepoel, Van Heerden, Carr, Gumede, Hanekom.

Replacements: Wessels, Smith, Klopper, Olivier, Ludwig, Johannes, Van der Walt, Hendricks.

Referee: Mathieu Raynal (Fra)