Who says 43o does not win?

PokerStars Game #25190821738: Tournament #142546416, $33.00+$1.50 Hold'em No Limit - Match Round I, Level III (25/50) - 2009/02/21 11:38:15 ET
Table '142546416 1' 2-max Seat #1 is the button
Seat 1: DRILLERONE1 (1360 in chips)
Seat 2: ouchbadbeat (1640 in chips)
DRILLERONE1: posts small blind 25
ouchbadbeat: posts big blind 50
*** HOLE CARDS ***
Dealt to ouchbadbeat [4s 3d]
DRILLERONE1: calls 25
ouchbadbeat: checks
*** FLOP *** [5h 6s 7d]
ouchbadbeat: checks
DRILLERONE1: bets 150
ouchbadbeat: calls 150
*** TURN *** [5h 6s 7d] [Ks]
ouchbadbeat: checks
DRILLERONE1: bets 300
ouchbadbeat: raises 1140 to 1440 and is all-in
DRILLERONE1: calls 860 and is all-in
Uncalled bet (280) returned to ouchbadbeat
*** RIVER *** [5h 6s 7d Ks] [Ac]
*** SHOW DOWN ***
ouchbadbeat: shows [4s 3d] (a straight, Three to Seven)
DRILLERONE1: shows [7s 8s] (a pair of Sevens)
ouchbadbeat collected 2720 from pot
*** SUMMARY ***
Total pot 2720 | Rake 0
Board [5h 6s 7d Ks Ac]
Seat 1: DRILLERONE1 (button) (small blind) showed [7s 8s] and lost with a pair of Sevens
Seat 2: ouchbadbeat (big blind) showed [4s 3d] and won (2720) with a straight, Three to Seven

This was friends game btw. He is such a luckbox lol.