Cryptic crossword

ACROSS

1. An Olympic event from Iceland is customary (6) 4. Upset hag sat looking horrified (6) 8. Amazing abilities of dominant nations (11) 10. Alison and I are involved in a relationship (7) 11. It’s a failure whichever way you look at it (3) 12. Ballad goes for a cheap price (4) 13. Electrocute young fish (3) 14. Ignoring the odds, guests are from the Russia of yesteryear (1,1,1,1) 17. Frenchman’s acceptance speech? (3) 18. Little Rod will grow up to be a frog (7) 19. Bargain hunter goes after unusual rags and jumper (11) 20. Early developmental stage bore my design (6) 21. Hopefully they will be well groomed (6)

DOWN

1. Objective is crudely done – is it a pass? (13) 2. Succeeding in being smart about higher plan (11) 3. Imaginary neural disorder (6) 5. Vegetables found on a golf course (6) 6. They may rain on one’s parade, but will show flashes of brilliance (13) 7. Condiment conveyed by cavalry transport is hard, unfortunately (11) 9. Team made strides but found a way round (11) 15. At first sinewy, then unusually meaty and hot (6) 16. 60Minutes admits no glory (6)