The domestic rivalry between double Olympic champion Rebecca Adlington and Joanne Jackson, world record holder, has given Britain two medal hopes in the 400m and 800m freestyle at the world championships in Rome next month. 

Adlington, Olympic 400m and 800m champion, won the Scottish 800m title in Glasgow tonight in 8mins 16.81 after a stroke-for-stroke battle with Jackson, second in 8:17.81, third best in the world so far this year. 

At the first round of world-championship trials in March, Jackson, Olympic bronze medal winner in the 400m freestyle behind Adlington in Beijing, set the world record of 4:00.66 over 400m in a race that also saw Adlington, swim inside previous world-record pace. Jackson's previous best was 8:23.87, while Adlington holds the world record at 8:14.10. The LZR Racer was worn for all of those swims.

The close battle at the British Gas Scottish Nationals came down to Adlington's faster last 100m, with Jackson, British 200m and 400m champion, unable to keep pace down the homecoming 50m.

"I really didn’t expect that time," said an unrested Adlington, coached by Bill Furniss at Nottingham. "It is the fastest I have been without resting and that's great. I wanted to stick with Jo as much as possible. It is so good that we push each other on. I wouldn’t want anyone else up there with me."

Jackson, coached by Kevin Renshaw at Loughborough, said: "I am pretty shocked by that. Becky pulled me through that race and it with only 100m left Becky pulled away and I didn’t have anything left. We help each other along and I really like having her there." The bronze medal went to a name to watch in future: Jazz Carlin, on 8:27.81.

In the 200m backstroke in Glasgow last night, Florida-based Gemma Spofforth, of Portsmouth, set a British record of 2:07.56. The standard had stood at 2:08.51 to Elizabeth Simmonds since last year. Spofforth's previous best was a 2:09.19, from the Games in Beijing.

"That just wasn’t expected," Spofforth said. "I thought I had a 2:09 I me but not a 2:07. It was just unbelievable. I felt quite tired this morning so that was very surprising. I think a few people will notice that performance." Stephanie Proud took to four the number of British women now inside 2:10, with a 2:09.79.

Olympic silver and bronze medallist and Jackson's training partner, David Davies, won a tight call with Robbie Renwick, of City of Glasgow, in a 400m freestyle final that ended 3:48.69 to 3:49.92.

In the midst of a programme of 10 events, Hannah Miley, coached by father Patrick at Garioch in Aberdeenshire, Scotland, continued to notch up fast times: in a 200m medley tussle with Olympic silver marathon medal winner Keri-Anne Payne, coached by Sean Kelly at Stockport, Miley claimed victory in 2:12.52, over 2:13.41.

"The schedule for Rome means that I will compete in the 10km first and so that will hopefully mean that I will have time to recover and refresh for the pool," Payne said. “It should work out well. I can’t choose which I prefer, open water or the pool, I enjoy them both."

Having missed the Olympic Games by a slither last year, London 2012 hopeful Marco Loughran made the grade for Rome with a 54.48 win in the 100m backstroke. The place was keenly fought for, Matthew Clay second on 54.58, with Matthew Bowe on 54.87.

The 50m free saw Francesca Halsall fall just 0.06sec shy of her best, on 24.59.