The pair last met last August at the European Championships when Thiam pipped Johnson-Thompson to title by 47 points, despite the Brit recording a personal-best points tally.
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Thiam holds all three major heptathlon titles and will head to the World Championships in Doha in September as favourite, but Johnson-Thompson could score a psychological blow when both compete in the long jump in Birmingham on August 18.
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The Liverpudlian out-jumped Thiam by eight centimetres at the Europeans last summer with an effort of 6.68m and has a personal best just short of seven metres.
Johnson-Thompson's GB team-mate Dina Asher-Smith will also compete in the Diamond League event in a star-studded 200m field.
Asher-Smith is the reigning European champion over 100m and 200m but is only the sixth-fastest woman in the world over the longer distance this year.

Dina Asher-Smith won three of Britain's seven gold medals in Berlin

Image credit: PA Sport

The 23-year-old will be far from favourite too because the field next month will also feature Olympic champion Elaine Thompson, world No 1 Shaunae Miller-Uibo and double world champion Dafne Schippers.
Asher-Smith finished fourth at the Worlds in London two years ago, missing out on a medal by just seven hundredths of a second.
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