Opening Day for the NFL is tomorrow! Neither team playing in the first game is in this puzzle, but six other teams are, and they are "built" by way of compound clues. As in, 24A: Frat dude + Cpls. and sgts. (BRO + NCOS = BRONCOS). Or, better yet, 50A: Butter square + Hilarious people (PATRIOTS). Excellent. The most obscure clue for me was the TI of TITANS ("Whatever You Like" rapper), but the crosses were more than fair. I like the theme, I like the revealer, TEAMBUILDING, and I like the bonus theme material - CHEERLEAD (18A: Root on) and KNEEL (37A: Take a stand by not standing).
Three other sports crowd into the puzzle, with TENTHINNING (11D: Bonus in baseball), NHLGAME (45D: Stanley Cup matchup, e.g.), and my favorite, 57A: Course overseer, for short (PGA).
The fill had a few rough spots. LUNISOLAR seems to be a thing, but it's not a super common thing, and I suppose UBUNTU is super common to many, but not to me. Add to that OAS (Organization of American States), ARI, NAE, ONES, TWOS, ORA and ORO, and you've got a noticeable amount of glue.
But then you've also got THEDOGATEIT (3D: Classic schoolkid's alibi), IVEGOTAPLAN (27D: "Hmm, leave this to me"), DATELINE (40D: It runs down the middle of the Pacific), and NOFEWERTHAN (25D: At least), which is kind of a lot of bonus long material.
On balance, I'm giving it a thumbs up. Turns out I was ready for some football.