The first appearance of Alex Jones and Jason Manford together on The One Show sofa drew in extra viewers last night.
Welsh presenter Jones's debut also proved a bigger draw than that of her predecessor Christine Bleakley's opening show three years ago.
Yesterday's eagerly-anticipated BBC1 show was watched by an average of 4.5 million viewers and a 23.5% share.
Bleakley, who has moved to ITV, was watched by 3.4 million (a 19.3% share) when she replaced Myleene Klass on, coincidentally, the same date - August 16 - three years ago.
Manford and Jones's first show, which drew a mostly warm response from critics, also beat the 2009 average for the teatime programme - which was 4.3 million viewers and a 21.6% share.
The show was also up on the equivalent Monday last year, August 17, which attracted 3.3 million (18.1%).
A delighted Jones, 32, said: "We're over the moon that so many viewers tuned in to watch our first appearance on The One Show last night and hope they all enjoyed it as much as Jason and I did.
"We were nervous before the show of course but Whoopi really helped by being such a great guest."