With four weeks of the NFL season in the books, you should have a good read on certain teams and situations. For example, stop underestimating the Bills and stop overestimating the Giants.

Underdogs went 9-7 against the spread (ATS) last week, and they would’ve been 10-6 if not for the ridiculous Chiefs cover on Monday night. That brings underdogs’ record to 36-26-1 on the season.

My most confident picks ATS this week are headlined by a trio of AFC East teams — Dolphins, Bills, Jets — followed by Lions, Eagles and Bears. A couple of tricky games to avoid: Chargers-Giants and Ravens-Raiders.

CHARGERS (0-4) AT GIANTS (0-4), 1 p.m.

TV: Ch. 2; Radio: WFAN (660, 101.9)

Giants by 3; O/U: 45

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Eli Manning and Philip Rivers will forever be linked to the ’04 NFL Draft. Now, their bond is 0-4. The only team to make the playoffs after an 0-4 start was the 1992 Chargers. The Giants and Chargers’ combined total of eight losses equal the six other NFC East and AFC West teams combined. The Giants have been close to a win, losing on last-second field goals at Philadelphia and Tampa Bay. They’ll be happy to be playing at MetLife Stadium . . . but it might be a welcome respite for L.A., too. After going 0-3 to start its new residence in the tiny StubHub Center, maybe playing at a real NFL stadium will give the Bolts a boost. Chargers pass rushers Melvin Ingram and Joey Bosa are a bad matchup for the Giants’ offensive line. Rivers and the Chargers usually play tight games, so expect another close one.

The pick: Chargers

JETS (2-2) AT BROWNS (0-4), 1 p.m.

TV: Ch. 5; Radio: ESPN (98.7)

Pick ’em; O/U: 39

Most predicted Cleveland would be improved, but the Brownies have shown they’re not ready to rise to even modest expectations. As for the Jets, many (including myself) didn’t give them a chance to win one game. Well, apparently all that outside noise has provided Gang Green with some Jet fuel because they’re playing with a chip on their shoulder the size of a boulder. After back-to-back home wins, there’s no reason to think they’ll let up against the winless Browns, a franchise that’s 1-22 in its last 23 games. Josh McCown was 1-10 as Cleveland’s starter, but he’s played well for the Jets. A win Sunday will give him a three-game win streak for the first time! The “tanks but no tanks” Jets continue to surprise and get to 3-2.

The pick: Jets

OTHER 1 P.M. GAMES

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JAGUARS (2-2) AT STEELERS (3-1)

Steelers by 8; O/U: 43

Pittsburgh’s offense got going at Baltimore last week, and it should continue at home. There’s little doubt the Steelers will win, but what about the spread? It’s a big number. Underdogs are 17-8 ATS this season when getting six or more points, and something tells me Jacksonville’s defense could keep this closer than most think.

The pick: Jaguars

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PANTHERS (3-1) AT LIONS (3-1)

Lions by 2; O/U: 43.5

You know what’s not funny, Cam Newton? The Lions’ defense. Detroit allows just 86.2 rushing yards per game and is second in the NFL with seven interceptions. In what figures to be a close contest in the fourth quarter — what else is new for the Lions — the edge goes to Matthew Stafford. Detroit does enough to win and cover, without having to worry about a last-second TD being overturned or not.

The pick: Lions

BILLS (3-1) AT BENGALS (1-3)

Bengals by 3; O/U: 39.5

How ’bout those first-place Bills? First-year coach Sean McDermott’s defense-first-second-and-third style has taken full effect as Buffalo leads the league with an NFL-low 13.5 points allowed per game. Last week’s stunning win in Atlanta put the rest of the league on notice. Andy Dalton and the Bengals rolled at Cleveland last week, but Cincy will struggle in this matchup. In the Bengals’ first two games, against similar ball-hawking defenses in the Ravens and Texans, Dalton threw no TDs with four picks and was sacked eight times in a pair of home losses. After frustrating Matt Ryan, the Bills will do the same to Dalton. Buffalo (one of only two teams 4-0 ATS) wins a low-scoring game.

The pick: Bills

LOCK OF THE WEEK

TITANS (2-2) AT DOLPHINS (1-2)

Titans by 2.5; O/U: OFF (QB)

If not for a touchdown on the final play against the Jets, the Dolphins would enter this game having been shut out, 20-0, in back-to-back games. Miami didn’t show up last week in London and the offense has been MIA. So why exactly are they the lock of the week? Ah, pull up a chair. First things first, this is their first game in Miami all season after the opener was postponed. Think about that: It’s Week 5, and this will be the players’ first chance to play before the home crowd. Think they’ll be pumped? Secondly, the Dolphins get a Titans team at the right time, as Marcus Mariota is unlikely to start because of a hamstring injury. If you want to lay points on the road with Matt Cassel, then be my guest. One more reason the Dolphins will roll: The Titans defense is allowing 31.5 points per game, the third-most in the NFL, and tied for the most TD passes with 11. Jay Cutler finally will get it going, throwing to Jarvis Landry and DeVante Parker as the Dolphins’ NFL-worst offense (8.3 points and 249 yards per game) has a similar offensive explosion as the Texans did last week. No, it won’t be 57 points, but — just like last week’s lock (sorry, Titans, nothing personal) — this is a perfect spot to take a team catching points at home in a game it needs to win.

The pick: Dolphins

CARDINALS (2-2) AT EAGLES (3-1)

Eagles by 6.5; O/U: 45

Arizona needed overtime to beat the Colts and 49ers, two of the NFL’s worst teams. Playing at Philly for a 1 p.m. start is tough enough. Throw in that the Cardinals played an extra 10 minutes last Sunday six days after a Monday night game and this has all the makings of the Eagles flying away early. Carson Wentz (7-2 at home) wins the battle of the Carsons as Philly’s defensive line gets after Carson Palmer.

The pick: Eagles

49ERS (0-4) AT COLTS (1-3)

Colts by 1; O/U: 44.5

The 49ers’ last three losses have been by 3, 2 and 3 points, and two of them were at Seattle and at Arizona (in overtime last week). Indianapolis is allowing an NFL-worst 34 points per game. Look for Carlos Hyde to have a big day as Kyle Shanahan earns his first win as an NFL head coach.

The pick: 49ers

4 p.m. GAMES & LATER

PACKERS (3-1) AT COWBOYS (2-2)

TV: Ch. 5

Cowboys by 2.5; O/U: 52.5

This is by far the best game of the week. The Cowboys definitely circled this one on the schedule, a chance to beat the team that went into their building and eliminated them from the playoffs last season. Aaron Rodgers and Green Bay jumped to a 21-3 lead in that NFC divisonal game before winning, 34-31, on a last-second field goal. This one should be close, too, and with a pair of beatable secondaries, the over is a good play as Rodgers and Dak Prescott will move the ball. So many times when you’re analyzing NFL games, it’s easy to focus on the “revenge factor.” But that strategy doesn’t always pay off (see: Green Bay’s Week 2 loss at Atlanta in a similar payback spot from last year’s NFC Championship Game). The Packers have been dealing with injuries, but the extra three days of rest having played last Thursday night could help. It’s not often Rodgers and the Pack are getting points, so put double checks next to Green Bay and consider it a discount.

The pick: Packers

SEAHAWKS (2-2) AT RAMS (3-1)

Rams by 1; O/U: 46.5

Even during the Jeff Fisher days, one guarantee was that the Rams played the Seahawks close. They’ve won three of the last four against Seattle, including the L.A. opener last season. The surprising Rams are 3-1 under 31-year-old coach Sean McVay, and fresh off an impressive win at Dallas. Seattle won big Sunday night, but it lost key players to injuries. Go with Jared Goff, Todd Gurley and the NFL’s highest-scoring offense (35.5 points per game) to win a close one.

The pick: Rams

RAVENS (2-2) AT RAIDERS (2-2)

Raiders by 3; O/U: 39

Derek Carr’s absence makes this a tougher call, but you still have to lean toward Oakland at home against Baltimore’s 30th-ranked offense. Plus, the Ravens have given up 70 points over the last two weeks. This should be low-scoring, so the under is a good play. Expect Oakland to find a way after back-to-back 10-point showings on the road, and hope for backup quarterback EJ Manuel to produce what his initials don’t: Points.

The pick: Raiders

SUNDAY NIGHT

CHIEFS (4-0) AT TEXANS (2-2)

TV: Ch. 4, 8:30 p.m.

Chiefs by 1; O/U: 45.5

Kansas City, the NFL’s only unbeaten team, also has a 4-0 ATS record thanks to the Monday night miracle cover. Deshaun Watson and Houston put up a 57-spot last week, and won’t be an easy out at home. The Chiefs probably would’ve been 3-point favorites had the Texans scored, say, 27 instead of 57, so take advantage of the slight break and bank on Alex Smith and the better all-around team grinding out a win for a 5-0 start.

The pick: Chiefs

MONDAY NIGHT

VIKINGS (2-2) AT BEARS (1-3)

TV: ESPN, 8:30 p.m.

Line; O/U: OFF (QB)

Bears fans get their first look at No. 2 overall pick Mitchell Trubisky, who showed promise at QB in the preseason and could give Chicago a much-needed boost. The Bears have looked like a different team at home, stunning the Steelers and nearly doing the same to the Falcons. The Bears upset the Vikings in a similar spot last Halloween, also a Monday nighter, and they could be primed for a repeat against a Minnesota team that lost its No. 1 running back Dalvin Cook.

The pick: Bears