In 1969 he played drums on the "flower power" pop single "Mr. Boyd" b/w "Imagine" by Argosy, a one-off group which also included Reginald Dwight (later known as Elton John), Caleb Quaye, and Roger Hodgson.

Subsequently, he played drums on one track on Elton John's debut album, Empty Sky, and then replaced Dave Hynes in The Spencer Davis Group, joining forces with bassist Dee Murray.

Olsson continued working as a studio musician, releasing another self-titled album produced by Paul Davis on Columbia in 1978, while managed by Martin Pichinson.

Although the album was critically successful, it failed commercially when their label, Artful Balance, went bankrupt, and the band was unable to tour to support the record.

On 31 March 2000, Olsson sang backing vocals alongside Billy Trudel and Ken Stacey when John appeared on The Today Show to promote the soundtrack to the film The Road to El Dorado.

On 3 April, Olsson played drums on three songs at the Broadway Cares/Equity Fights AIDS benefit saluting John at the New Amsterdam Theatre in New York City.

By the time of John's "One Night Only" concerts in New York City on 20 and 21 October, Olsson was alternating with and playing drums alongside Curt Bisquera.

He then played all the drums on Peachtree Road (2004) and The Captain & the Kid (2006), as well as continuing in the touring band, along with Johnstone, Bob Birch (bass), Kim Bullard (keyboards) and John Mahon (percussion).

With bassist Matt Bissonette replacing the late Bob Birch in 2012, this band recorded Wonderful Crazy Night in 2015 for release in February 2016.

[5] On his 68th birthday, 10 February 2017, Olsson played his 2,267th concert with Elton John at The Colosseum at Caesars Palace, Las Vegas, Nevada.