The Browns might be for real. The Colts, too.

We could find out on Sunday, when Indianapolis visits Cleveland. Both teams are 3-1, winners of three in a row, and carrying questions about who they have beaten.

The Browns were pummeled by Baltimore before defeating Cincinnati, Washington and Dallas, combined record 3-8-1. Indy lost badly at Jacksonville, which since has dropped three in a row, and then defeated Minnesota, the Jets and Chicago, combined record 4-8 headed into Week 5.

This matchup could prove something, with Cleveland's dynamic offense facing the league's most stingy defense.

“This will be our defense’s biggest challenge. You’ve got the No. 1 offense as far as running the ball,” Colts coach Frank Reich said. “The other thing that they are No. 1 at is explosive plays in the run game. We’ve got the No. 1 defense so this is what it’s all about. We’ll see how it stacks up.”

Indeed, says Browns quarterback Baker Mayfield, who won't have leading rusher Nick Chubb (knee).

“They are a really sound defense. They play together. They are coached well. They hustle. You can see the effort. They swarm to the ball.”

The action began Thursday night with Chicago's 20-19 home victory over Tampa Bay. Nick Foles beat Tom Brady again, Cairo Santos kicked a 38-yard field with 1:17 left and the Bears held on when Brady seemingly lost count of downs on his final play.

Detroit (1-3) and Green Bay (4-0) had byes.

Philadelphia (1-2-1) at Pittsburgh (3-0)

The Pennsylvania showdown matches two first-place teams. Say what?

Yep, the Eagles are atop the wretched NFC East, displaying the kind of grit and resourcefulness any fan base should be proud of. And possibly proud of in the City of Brotherly Love — until they lose again.

Pittsburgh was off last week while planned opponent Tennessee deals with a COVID-19 outbreak. Fans are allowed at Heinz Field for the first time this season after Pennsylvania officials amended occupancy guidelines at outdoor events. Capacity will be capped at 5,500 at the 67,000-seat stadium.

Buffalo (4-0) at Tennessee (3-0), Tuesday night

The Bills and Titans might need another Music City Miracle to actually play this game, which has been moved to Tuesday. The Titans' coronavirus outbreak, which forced postponement of their matchup with the Steelers last week, has wreaked havoc ever since.

If they play, well, anything close to the 2000 playoff game Tennessee won with that incredible razzle-dazzle kickoff return would be refreshing.

The Bills are 4-0 for the first time since 2008 and looking to start 5-0 for the first time since 1991 on their way to a Super Bowl berth. A victory also would give the Bills their first five-game winning streak since 2004.

The Titans are 3-0 for the first time in 12 years. About 8,500 fans or approximately 12.5% of capacity will be allowed at this game — if it comes off.

Denver (1-3) at New England (2-2), Monday night

Cam Newton and Stephon Gilmore, possibly the Patriots' two best players, have tested positive for coronavirus. New England comes off a mediocre offensive performance at Kansas City, but the Patriots have won six of the past seven meetings between the teams, including four straight in Foxborough. The Broncos haven’t won a road game in the series since 2006, and get an extra day to prep with the NFL moving this one a day because of the Patriots outbreak.

Denver linebacker Bradley Chubb led the league with 10 quarterback pressures last week in a win over the Jets. He had 2½ sacks, his first takedowns since returning from a torn ACL.

Las Vegas (2-2) at Kansas City (4-0)

The Raiders have dropped two straight, and this isn't a good place to turn it around. They have lost their past seven games at Kansas City and five straight in the series overall.

“It will never be easy,” said quarterback Derek Carr, who has nine turnovers in six games at Arrowhead Stadium, leading to a miserable 63.2 quarterback rating. “We haven’t won there in some time as an organization. We need to get a win there.”

Meanwhile, the Chiefs are 4-0 for the fourth straight season, an NFL mark. They are trying to start 5-0 for the third time in four seasons, have won a franchise-record 13 consecutive games, and their 10-game regular-season winning streak is the second best in club history. Plus, KC has won 28 of the past 30 games against the AFC West.

Cincinnati (1-2-1) at Baltimore (3-1)

Joe Burrow looks like the real thing: He has three straight 300-yard passing games, a rookie record. And his top running back, Joe Mixon, has been a stud.

That said, the Bengals, coming off their first win following a tie, face a difficult test in Baltimore. The Ravens are 26-11 against the AFC North at home under coach John Harbaugh, who took over in 2008. Baltimore is 73-25 overall at home under Harbaugh.

Two of this year's most productive kickers will be featured. The Ravens' Justin Tucker is 8 for 8 on field goals and owns an NFL career-best 91% success rate on FGs. Cincy's Randy Bullock is tied for the NFL lead in scoring with 45 points.

Miami (1-3) at San Francisco (2-2)

San Francisco is 0-2 at home, 2-0 at the New Jersey Meadowlands. Huh?

The Niners can't keep struggling in the league's toughest division, where Seattle already is 4-0. But at least the 49ers are getting healthier on both sides of the ball.

Miami is playing decently despite its record, outscored only 96-93. The game is the Dolphins’ first in San Francisco since 2012, and their first on the West Coast since 2017.

Los Angeles Rams (3-1) at Washington (1-3)

Ron Rivera has benched the Washington franchise's supposed future quarterback, Dwayne Haskins, for Kyle Allen. Apparently the team has run out of patience with Haskins' slow education in the offense.

No such woes in LA, where the Rams' attack is humming behind Jared Goff and his collection of receivers. Believe it or not, this is the Rams' third trip to the Atlantic side of the nation already.

Minnesota (1-3) at Seattle (4-0)

Despite a bunch of gambles and a hole-filled defense, the Seahawks are off to a terrific start. They have never been 5-0, and the previous time they took their first four games, they went on to win the Super Bowl.

Russell Wilson tied Peyton Manning’s record with 16 TD passes in the first four games of a season. Wilson has a 113.5 career passer rating in five games against the Vikings.

Minnesota has never beaten Seattle coach Pete Carroll, dropping six in a row vs. the Seahawks since a 2009 win. Dalvin Cook leads the league in rushing yards (424) and has a career-high average of 5.7 yards per carry. Seattle defends the run well, but ranks last in pass defense.

New York Giants ( 0-4) at Dallas (1-3)

Remember when NBC would showcase this matchup in prime time early in the schedule? Luckily for the network, it didn't go there in 2020.

The Cowboys and Giants are meeting with the lowest combined winning percentage (1-7, .125) in the series through at least four games. The Cowboys have won six consecutive games in the 60-year rivalry, their longest streak since winning 12 in a row from 1974-80.

New York has trouble scoring and Dallas can't stop anyone.

Los Angeles Chargers (1-3) at New Orleans (2-2), Monday night

A game that at one point could have been headed elsewhere as Hurricane Delta threatened the Big Easy. It will happen in the Superdome, where the Saints could get back their key weapon, 2019 Offensive Player of the Year Michael Thomas. The star receiver's ankle injury damaged the offense in two losses before New Orleans scored five straight TDs at Detroit for a victory.

The Chargers have dropped five consecutive Monday night games and will be missing RB Austin Ekeler (hamstring injury). Rookie quarterback Justin Herbert has been inconsistent but not overwhelmed.

Arizona (2-2) at New York Jets (0-4)

Things looked so bright for the Cardinals with their 2-0 start. Then they fell to Detroit and Carolina, not exactly playoff contenders. Of course, the Jets seem like the leading contender for the first overall draft choice.

Kyler Murray tops NFL quarterbacks with 265 yards rushing and is tied with New England’s Cam Newton with four TD runs. DeAndre Hopkins leads the NFL with 39 catches, and veteran Larry Fitzgerald has no TD catches against the Jets — one of only three franchises to blank him. Look for that to change.

New York is without QB Sam Darnold (shoulder), which means Joe Flacco tries to get something done.

Jacksonville (1-3) at Houston (0-4)

Firing a coach early in a season like this, disrupted by a pandemic, seems pretty harsh. Nevertheless, Bill O'Brien is out in Houston, with Romeo Crennel becoming the league's oldest head coach at age 73. The talent seems to be there for the Texans, but they rank last in rushing offense AND defense.

Jacksonville has dropped three in a row in 2020 and four straight to the Texans.

Carolina (2-2) at Atlanta (0-4)

Another defeat could send Atlanta's Dan Quinn packing like O'Brien, and the Falcons' winless start is just as puzzling. Blame everything from a sieve of a pass defense to folding in the fourth quarter to poor coaching.

Still, they have won five straight and eight of the past nine in the series.

Carolina, however, has shown lots of spunk under rookie head coach Matt Rhule, winning two straight and getting solid offensive contributions from everyone in the absence of 2019 All-Pro running back Christian McCaffrey (ankle).

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