The man himself – then a few months from turning 37 and struggling to get regular games with Everton after almost eight years there – even thought that was the case.
But when the veteran defender left Ibrox some five years later with eight major honours behind him, he did so as a Light Blues legend.
Weir was a player Smith had always liked and it was him who had captured the Scotland international from Hearts when he was in charge at Goodison Park.
He had also convinced the former Falkirk star to return to the international fold when he replaced Berti Vogts as Scotland manager.
It was therefore logical for Smith to move for Weir, someone he knew well and trusted to do a job for him, to shore up an uncertain-looking Rangers defence.
Paired with Ugo Ehiogu, another mid-season addition, Weir helped restore some respectability at Ibrox in the remainder in the 2006/07 after Paul Le Guen’s ill-fated tenure.
But what followed afterwards was remarkable as he teamed up with Spaniard Carlos Cuellar the following campaign to almost pull off arguably the finest result in the club’s history.
Rangers’ run to the 2008 UEFA Cup final against Zenit St Petersburg in Manchester was notable for many things after their exit from the Champions League at the group phase.
One of them was the team’s sound defensive foundations and while the football wasn’t always pretty, it was certainly effective as it got results.
Weir and Cuellar were rocks at the back as they kept out Panathinaikos, Werder Bremen and Sporting to steer their team into the semi-finals.
At that stage, the central pairing was magnificent once again as it resisted everything Fiorentina threw at it to force a penalty shoot-out.
Gers won thanks to Nacho Novo’s deciding kick but the game with the Russians was a step too far as they won 2-0.
By that stage the Ibrox team had run out of steam and the league eluded them too, although both the Scottish Cup and League Cup – Weir’s first Gers honours – were secured.
It was important to bounce back in the right manner in 2008/09 and after a sluggish start, Rangers claimed their first title on the last day with a 3-0 win at Dundee United.
By now, Weir was sporting the captain’s armband having replaced Barry Ferguson temporarily and he hoisted the trophy aloft with the midfielder at Tannadice.
The stopper would repeat that feat a few days later as Falkirk were beaten in the Scottish Cup final courtesy of more intervention from Novo.
Weir was soon the skipper on a permanent basis, signing one-year deal after one-year deal along the way, after Ferguson moved on to Birmingham.
A natural leader, the endurance he was showing in spite of his age – and constant focus on how old he was in the media – was admirable.
It said much about the levels he reached that after Rangers retained their title in 2010, he was named as the Scottish Football Writers’ Player of the Year days before he turned 40.
The Ibrox team also took the League Cup that season with a stunning 1-0 win over St Mirren despite being reduced to nine men.
It was one of the most memorable victories Smith had in his second spell in charge of the club and it was a game in which Weir’s experience was absolutely vital to see the team home.
There were to be two more trophies for the former Scotland international in 2010/11, with the first another to savour.
This time, however, Weir wasn’t tested quite as much as Rangers had the better of a derby meeting with Celtic in the League Cup.
For all that, it took until extra-time for Nikica Jelavic to get a deserved winner which hit one post then sneaked over the line before it hit another for give his team a 2-1 success.
The title was next for Rangers and it took until the final day to clinch it – but the team did so in some style.
Weir played a part in the opener as Gers romped into a 3-0 lead at Kilmarnock after less than six and a half minutes and an eventual 5-1 rout made it three in a row.
Smith had already signalled his intentions to leave at the end of that season and it was widely expected Weir would move on too.
He surprised many by choosing to stay a little longer but played just once more against Malmo in a Champions League qualifier before injury got the better of him.
Weir made 231 competitive appearances and scored five times, a quite phenomenal tally when you consider he arrived as someone considered to be in the twilight of his career.
His knowledge and advice is recognised to have played a significant role in the impressive Ibrox stays of Cuellar, Madjid Bougherra and, to a lesser extent, Danny Wilson.
Weir left Rangers in January 2012 to take up a role with former club Everton coaching their reserve and youth sides.
He won 69 caps in all, scoring once against Latvia, in an international career spanning over 13 years.
David Weir (2007-12)
Appearances: 231. Goals: 5.
Honours: three league titles, two Scottish Cups, three League Cups.
69 caps (Scotland).