Theme: Feet - Various types of kicks (that you make with your feet).
16A. *Mark of a hothead : QUICK TEMPER. Quick kick - Surprise punt.
38A. *"This space available," in a Pennysaver box : PLACE YOUR AD HERE. Place kick - Placing the ball on the ground at a particular spot and usually kicked for points.
10D. *Relaxed : FREE AND EASY. Free kick - Restart play without any defensive pressure.
24D. *A football referee may throw one : PENALTY FLAG. Penalty kick - One on one, kicker versus goalie.
57A. Foot-operated mechanism on a motorcycle, and what the first word in each answer to a starred clue can be : KICK STARTER. I haven't seen anyone kick start a Harley in sometime. (From C.C.: My original clue is "Giant in crowdfunding, and what the first word in each starred answer is")
Rabbit Rabbit Argyle here. C.C. getting her kicks. (I hope she's feeling better) Grid span surrounded by long theme answers. Some unexpected difficulties.
Across:
1. Greenhouse growth : PLANT
6. Condescending one : SNOB
10. Take wing : FLY
13. Andrea __: sunken ocean liner : DORIA
14. "So I was wrong!" : "SUE ME!"
15. Actor Stephen : REA. Have we learned him yet?
18. "A mouse!" : "EEK!"
19. Remain fresh : KEEP
20. North African port city : ALGIERS
22. Regret one's 32-Acrosses : REPENT of 32A. Admission in a confessional : SIN
25. Cavs, on scoreboards : CLE. (Cleveland)
26. Blurt out : SAY
27. Figure skating jump : AXEL
28. NYC airport named for a mayor : LGA. Fiorello La Guardia was New York City's mayor from 1934 to 1945.
30. One of two matching beds : TWIN
33. Hotelier Helmsley : LEONA. 'Queen of Mean'
35. Lady's title : MADAM
41. Peddles : SELLS
42. Fight mementos : SCARS
43. Crunched muscles : ABs
44. Dog who reveals the Wizard : TOTO. Still not in Kansas.
46. Netherlands airline : KLM
47. Those, to Pedro : ESOS
48. Procedure: Abbr. : SYS. (system)
49. Stamp sellers, briefly : POS
51. Ancient scrolls : PAPYRI Written on paper made from papyrus.
53. Takes over, like termites : INFESTS
55. Menu item : DISH
56. Baseball's "Iron Man" Ripken : CAL. Ripken broke Lou Gehrig's record for consecutive games played, a record that had stood for 56 years and many deemed unbreakable. Cal had 2632 consecutive games. 2D. Baseball's "Iron Horse" Gehrig : LOU. 2130 consecutive games.
62. Pitcher's stat : ERA. (Earned Run Average)
63. Online letter : E-MAIL
64. Accord automaker : HONDA
65. Brain scan, for short : EEG
66. Put on notice : WARN
67. Being hauled to the garage : [IN TOW]. Often a sign in the back window.
Down:
1. ASAP cousin : PDQ. (As Soon As Possible/Pretty Damn Quick)
3. Tycoon Onassis : ARI. The Greek who married Jackie.
4. Five-cent coin : NICKEL
5. Unavailable : TAKEN
6. Total : SUM
7. Himalayan country : NEPAL
8. Brunch order : OMELET
9. Arctic hazard : BERG
11. Suspicious : LEERY
12. Chews the fat : YAKS
14. Back-to-school mo. : SEP. (September)
17. Lipton shelfmate : TETLEY. Teas.
21. Basketball Hall of Famer Thomas : ISIAH. Update: On top is ISIAH, on the bottom, ISAIAH. He was named after the Hall of Famer but his father is James Thomas. Thanks go out to Jim P. and Lime Rickey and Middletown Bomber for straightening things out.
22. Filing tools : RASPS
23. Formally banish : EXILE
25. Vancouver NHL team : CANUCKS
29. Baby talk syllables : GOOs
31. Alleged Iraqi arsenal, for short : WMDs. (weapon of mass destruction)
33. "__ we forget" : LEST
34. Sea divided by shrinkage : ARAL
36. Leafy recess : ARBOR
37. FC Barcelona soccer star Lionel : MESSI. Knows how to kick.
39. Nearby : CLOSE
40. Deodorant spot : ARMPIT
45. Kia sedan : OPTIMA
47. "Sleepless in Seattle" director Nora : EPHRON
48. Game trap : SNARE
50. "The Odd Couple" slob : OSCAR. (Oscar Madison)
52. Japanese beer brand : ASAHI
53. Slurpee alternative : ICEE
54. Distort : SKEW
55. Broadband letters : DSL. Better than dial-up.
58. Family : KIN
59. Blasting material : TNT
60. Tokyo, long ago : EDO
61. Like unprocessed data : RAW
Argyle