Across:
8. State to quash Miami photo finishes (4)
9. Fills in as new first in line in rowing team before finals of the qualification races (10)
10. Strange willingness to accept perversely dirty clue (9)
11. Quickly write about popular venue (5)
12,27. Bird 5 mostly scrambled for 1 21 (3 3)
13. Abandons in deep 27s (7)
15. Taking in me, down and out guy, unknown, is being a member of my community (7)
16,4dn. Little guy in boat race quietly passed and 1 21 won it (3 5)
17. Part of Rio's a Kazakh city with Asian residents (5)
18. Face vessel - one with much 10? (3)
19,2dn. Who's rock opera would sound before one crows in the morning for final trainer with 1 21? (5 8)
21. see 1 down
23. Nasty scare in substance that might have killed 1 21 (7)
26. Imprisonment is part of toxic US to dying (7)
27. see 12 across
29. Let adults only win about 50-50 (5)
30,16dn. Minor 11 almost gets Ashes trophy, turning purplish 27 as... 1 21 won it! (9 3)
33. Sad city blokes part of database (10)
34. see 11 down
Down:
1,21ac. Wonder horse with firsts in pretty hard arse races, lastly annual Tijuana handicap (4 3)
2. see 19 across
3. see 25
4. see 16 across
5. Estate's last horse... good source of protein? (3)
6. Minion, at heart, feels too gentle (6)
7. Not told of "neutral" invading wearing military outfit (10)
:11,34ac. Who was usually on top of 1 21? Judge and one politician: Eisenhower (3 4)
12. Steer south of black hedge (3)
14,28. Arterial busy and chaotic, a Sydney race and 1 21 won it! (10 5)
15. Animal with pathogens in heart (3)
16. see 30 across
18. Coat for truck (3)
20. Performs better in "Spring Carnival" perhaps, but joust ruined with official involved (8)
21. 12 down might have one, or 51,500 (3)
22. Vessel of rum? Belt loosened! (7)
24. Some bloke rode sheep and wears down (6)
25,3. Fresh enthusiasm and 1 21 came from here (3 7)
28. see 14
31. Where many runners are from, some seeking to return (4)
32. Rough accommodation for the 15 down - no alternative in this story? (3)
Solution:
=P=W=Z=P=E=S=U=|
OHIO=ENLIGHTENS|
=A=O=A=A=G=O=I=|
CREDULITY=JOINT|
===C=A=E=BIG=F=|
MAROONS=HOMEBOY|
=U=C=D=COX===R=|
OSAKA=MUG=TOMMY|
=T===LAP=T=U=E=|
ARSENIC=CUSTODY|
=A=RED=D=M=J===|
ALLOW=MELBOURNE|
=I=D=S=R=L=M=I=|
LAMENTABLE=PIKE|
=N=S=Y=Y=R=S=E=|
Name: 926 - Hard Arse Racer
Author: by BenDR

Annos-Across:
8. tails (t)O (quas)H (miam)I (phot)O
9. ( N L(ine) ) in EIGHT + tails( (th)E + (qualificatio)N (race)S )
10. *( DIRTY CLUE )
11. IN in JOT
12,27. *( BIRD EG(g) )
13. dd
15. ME in HOBO + Y
16,4dn. COX + P + LATE
17. tel (ri)O'S A KA(zakh)
18. ddd
19,2dn. TOMMY + hp( WOULD ) + COCK
23. *( SCARE IN )
26. tel (toxi)C US TO DY(ing)
29. LL in ( AO + W )
30,16dn. M + ELBO(w) + URN + rev( PUCE )
33. LA + MEN + TABLE
Annos-Down:
1,21ac. P(retty) H(ard) A(rse) R(aces) + (annua)L (tijuan)A (handica)P
5. (estat)E + GG
6. middle of "(feel)S TOO GE(ntle)"
7. N in UNIFORMED
:11,34ac. J + I MP + IKE
12. B + OX
14,28. *( ARTERIAL BUSY AND )
15. middle of (pat)HOG(ens)
18. dd
20. UMP in *JOUST
21. LI + D
22. *( RUM BELT )
24. tel (blok)E RODE S(heep)
25,3. NEW ZEAL + AND
31. rev tel (se)EKIN(g) <
32. ST(or)Y
Defs-Across:
8. State
9. Fills in
10. Strange willingness to accept
11. venue
12,27. 1 21
13. Abandons
13. deep 27s
15. a member of my community
16,4dn. 1 21 won it
17. city with Asian residents
18. Face
18. vessel
18. one with much 10
19,2dn. final trainer with 1 21? 
23. that might have killed 1 21
26. Imprisonment
29. Let
30,16dn. 1 21 won it!
33. Sad
Defs-Down:
1,21ac. Wonder horse
5. good source of protein?
6. Minion
7. Not told
:11,34ac. Who was usually on top of 1 21?
12. hedge
14,28. a Sydney race and 1 21 won it!
15. Animal
18. Coat
18. truck
20. Performs better in "Spring Carnival" perhaps
21. 12 down might have one
22. Vessel
24. wears down
25,3. 1 21 came from here
31. Where many runners are from
32. Rough accommodation for the 15 down