Quarterback AJ McCarron reached XFL season highs with 420 passing yards and six touchdown passes in the St. Louis Battlehawks’ 53-28 victory over the Orlando Guardians on Saturday.

Entering the regular-season finale tied with the Seattle Sea Dragons for the second playoff spot in the XFL’s North Division and facing a tiebreaker that likely would go to rankings in points scored and points allowed, the Battlehawks offense did its part.

St. Louis punted on its first possession and missed a field-goal attempt on its last one. But on the eight in between, the Battlehawks scored at the Dome at America’s Center.

St. Louis fell behind three times in the first half but reached halftime with a 25-20 lead.

Former South Alabama running back Kareem Walker scored from 1-yard out on a fourth-down snap as the Battlehawks took a 9-6 lead with 12:27 left in the first half.

After Orlando punter Mac Brown threw an 84-yard touchdown pass to tight end Jordan Thomas, McCarron connected on a 6-yard touchdown pass to wide receiver Hakeem Butler as St. Louis took a 17-12 lead with 6:36 left in the first half.

On Orlando’s next snap, Quinten Dormady threw a 45-yard touchdown pass to wide receiver K.D. Cannon. But the Battlehawks got the lead for good on a 5-yard touchdown pass from McCarron to tight end Jake Sutherland with 55 seconds left in the first half.

St. Louis’ first four second-half possessions ended in McCarron touchdown passes – 13 yards and 16 yards to wide receiver Steven Mitchell, 66 yards to Butler and 4 yards to wide receiver Darrius Sheppard.

The former Alabama All-American completed 28-of-35 passes for 420 yards with six touchdowns and no interceptions. He also completed four 2-point conversion passes.

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St. Louis and Seattle had 6-3 records entering the Week 10 schedule. The Sea Dragons must beat the Vegas Vipers in the final game of the regular season at 6 p.m. CDT Sunday to keep pace with the Battlehawks.

If that happens, the first three tiebreakers – head-to-head, division record and strength of victories – won’t break the tie.

The fourth tiebreaker is best combined ranking among division teams in points scored and points allowed.

Comparing St. Louis to the D.C. Defenders, Sea Dragons and Vipers, the Battlehawks are second in points scored with 249 and second in points allowed with 202.

The number to keep in mind for Sunday night’s game is 34. St. Louis has scored 34 more points and yielded 34 more points than Seattle. The Sea Dragons have given up 168 points and the Vipers have scored 175 points in nine games this season, so it would appear unlikely that Vegas would score the necessary number to allow the Battlehawks to move up to No. 1 in the division in points allowed.

But if the Seattle also doesn’t score 34 points against Vegas, the Sea Dragons and Battlehawks would remain tied, and the fifth tiebreaker – best combined ranking among all teams in points scored and points allowed – will come into play. While second in the XFL in points scored with three games left on the league schedule, St. Louis is fifth in points allowed. Seattle is fourth in points scored and first in points allowed.

Mark Inabinett is a sports reporter for Alabama Media Group. Follow him on Twitter at @AMarkG1.