Scotland outgunned the Pacific Islanders in the second autumn Test at Murrayfield but were not in any mood for a party after the final whistle.
The 34-22 triumph was soured by two serious-looking injuries in the build-up to the RBS 6 Nations Championship and the 2007 World Cup.
Scrum-half Chris Cusiter and breakaway forward Johnny Beattie were taken to hospital after being carried off in the opening 10 minutes.
Border Reivers man Cusiter appeared to have sustained a shoulder injury, while Beattie suffered a suspected ankle fracture - a week after marking his first cap with a try.
The other big concern for Scotland head coach Frank Hadden was his side's failure to ram home their superiority in the second half after leading by 26 points at the break.
The Scots, buoyed up by their runaway triumph over Romania, made a storming start - underlining their intention to keep the ball alive whenever possible.
Recalled stand-off Dan Parks steadied his nerves with a long touch-finder and then Scott Murray stole the lineout, paving the way for Sean Lamont to come infield and embark on a surge down the middle.
Visiting full-back Norman Ligairi had to look lively to prevent Simon Webster from being first to reach a chip into the danger zone.
Webster was back in the spotlight just two minutes later when he set off in pursuit of his own kick, but again he was beaten in the race.
Then came number eight Beattie's moment of agony as he was carried off on a stretcher following a big hit at the base of a ruck by Tongan prop Taufa'ao Felise.
Callam entered the fray and made an instant impression by ploughing over the line from the fragmented tail of a lineout, but he could not get the ball grounded.
Seconds later centre Marcus di Rollo darted through a half-gap in midfield to snap up the first try.
Chris Paterson slotted the simple conversion - but there was no sense of celebration in the Scots camp as they were rocked by their second major injury blow.
Scrum-half Cusiter was the casualty with what looked like a recurrence of a shoulder problem after a robust challenge by flanker Viliami Vaki.
On came his friend and rival Mike Blair with the aim of helping Scotland maintain their early momentum.
They did just that as a marvellous long pass by Parks left three visiting defenders marooned, allowing Callam - lurking on the right-hand touchline - to gleefully beat off Tusi Pisi's tackle and dive over in the corner.
The conversion was from the widest possible angle, but Paterson made it look like a formality.
The Islanders were rocked by three further setbacks in quick succession.
Back-row man Epi Taione was yellow-carded for a ruck offence seconds before Kelly Brown galloped in for try number three from close range.
Then centre Andy Henderson flopped over for another after the unlucky Webster was brought down only a pace short of the target. Paterson preserved his 100% record with the boot to give Scotland a 28-point cushion.
Taione returned to the action and immediately the visitors broke their duck with a touchdown by Fijian cult hero Rupeni Caucaunibuca, capitalising on good work by Pisi.
There was still time before the interval for Paterson to thump over a penalty from almost 50 metres.
But the Scots were made to pay for defensive lapses after the restart.
First, centre Kameli Ratuvou pounced when Lamont meekly surrendered possession inside his own half with no supporting players around him.
Then lock Daniel Leo finished in style at the end of a fast and clinically executed handling move down the centre of the field.
Lamont thought he had made amends, but the referee had blown for a Scotland penalty a split second before he touched down.
Caucau had home alarm bells ringing again with a trademark sprint out of his own 22 and into enemy territory, but Lamont backtracked heroically to snuff out the immediate danger.
The visitors appeared to tire going into the final quarter as the Scots set up camp close to the line.
But they could not turn constant pressure into instant points, allowing the Islanders to retain a glimmer of hope.
Parks was blocked a metre short and Nathan Hines was held up over the line.
And the frustration of Scotland was underlined when Di Rollo was reduced to notching their first and only points of the half with a drop-goal three minutes from time.
The visitors refused to buckle and Ratuvou completed his double, Pisi adding the conversion.