The pony-tailed former Croatia forward secured victory with a 66th-minute header that allowed the new Ibrox manager to savour success in the opening game of his side’s Bank of Scotland Premierleague campaign. Le Guen has been given the task of revolutionising Rangers after the decline that consumed Alex McLeish, and the Frenchman put out a side that had eight changes from the one his predecessor signed off with last May.

One of the new recruits, Libor Sionko, launched the era with an eighth-minute goal but it was the talisman from the ancien regime, Prso, who made the most telling contribution.

Rangers almost paid for their first-half profligacy, though, when they tore Motherwell apart, and relied on Prso to restore their lead after Phil O’Donnell’s fine equaliser.

“We came to get three points,” Prso said. “The performance was fine but we have to do better in our finishing.” However, Le Guen, whose new training routines are noted for their severity, chose to show some compassion for his side. “We missed many chances but it does not matter,” the new Rangers manager said. “We played very good football and even after Motherwell equalised we never gave up. It was a very good game and we were well-rewarded. There was good pace and rhythm and a good relationship between my players.”

Across in the other dugout, Maurice Malpas began his own reign as Motherwell manager with a similar feeling of frustration to the one that his friend and predecessor, Terry Butcher, took with him when he departed to Sydney in June. Motherwell — without several recognised defenders — pushed Rangers to the brink but could find no reward.

“It could have been 4-0 to Rangers after 20 minutes,” the honest Malpas said. “We rode our luck. We sat back and admired Rangers and watched them play. The second half was a different story and we caused them problems. However, I was disappointed to lose the second goal to a set-piece. The pace of the game was unbelievable. It was 1,000mph but Rangers handled it well.”

The first 45 minutes of Le Guen’s reign were truly breathtaking. Rangers ought to have swept Motherwell aside with the torrent of pressure that their fierce tempo brought. They had seven clear chances and the only flaw was that — Sionko apart — they failed to take any of them and put the game to bed.

It was not just the changes from McLeish’s swansong, there was also a difference in attitude. Rangers players were given freedom to express themselves in Le Guen’s 4-2-3-1 system but they also swapped positions so often that it was hard for Motherwell to guess what was going on. When they had the ball, Rangers resembled 4-4-2 but when the lost it, five men funnelled back into midfield where the fierce pressing game gave the hosts little time to build.

The only goal of the first half came after just eight minutes. A clever diagonal pass from the impressive Charlie Adam — recalled after a loan spell at St Mirren — tore Motherwell open and Sionko’s well-timed run gave him a sight of goal. Graeme Smith, the goalkeeper, came out to meet the Czech and was unfortunate to see his attempted clearance come back off Sionko and creep over the line.

However, if there was fortune attached to that goal, it was Motherwell who rode their luck until the interval. Thomas Buffel, for instance, passed up four good chances. The Belgium player began just before Sionko scored, when he exposed Bobby Donnelly, Motherwell’s young centre-back, and rounded Smith only to see Donnelly and Jim Paterson combine to repel his shot.

Just after the half-hour, Buffel had an even more glaring miss when he ran 60 yards after Ross Mcormack — released by Le Guen from Ibrox and keen to prove a point on his debut — had threatened to net his first Motherwell goal at the other end. Buffel skipped past the lone defender, Stephen Craigan, in the centre circle, and with a posse of five amber shirts chasing him he advanced on Smith, only to loft the ball over the bar.

Sionko was guilty of wasting a perfect chance five minutes before the break when Prso set him up with a sublime pass in behind Paterson but the Czech headed over the bar.