Across:
   1. Sprinter allowed to enter heat (7)
   5. About 100 may be fit to join up again (7)
   9. Enormous guys enter poor semi (7)
  10. Bird has a run inside for one month (7)
  11. Joining up points left one hurt (9)
  12. Girl is partly intruding (5)
  13. Father becomes teacher, in time (5)
  15. Basic material for up to 1000 new clay pots (9)
  17. Dr Hill may be leading southern travellers (9)
  19. Locks in swimmers (5)
  22. Spurt of oil (5)
  23. Sensible Pam is involved in tragic crash! (9)
  25. More dangerous when covered more thickly (7)
  26. Aged men may be in final phase (7)
  27. Caused ineffectual journalist to take Rex in (7)
  28. Writer lost broken plaything (7)
Down:
   1. Denise adds a flavouring (7)
   2. Reduced noise leaked out (7)
   3. Endlessly serene birds (5)
   4. Points out the old religious eastern church for viewers (9)
   5. Modify dance again? (5)
   6. Monuments to Eton chaps? (9)
   7. Enthusiasm shown by supporter near old city in Virginia (7)
   8. Yes, muesli can be heaven! (7)
  14. Measure two poles (9)
  16. Will has the last word between trial and start of tribunal (9)
  17. Scholar's cut out dry old writer (7)
  18. I call Lawrence outside to see woodworm (7)
  20. Draw in by pamphlet (7)
  21. Home counties battle for privacy (7)
  23. Trimmed drape (5)
  24. Doctor Derek is a poser! (5)