Four games do not make a season, but they can show trend and development.

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Baker Mayfield has started four games for the Cleveland Browns, one-quarter of a season, and played just more than one half of a fifth. He's 1-3 as a starter but led the second-half comeback against the Jets in Week 3.

An overall look at Mayfield's numbers shows some positives and some reasons for concern. A deep dive into his numbers might be most revealing about the challenges a rookie quarterback faces.

Mayfield's rating after the loss in Tampa Bay was 78.5, 29th in the league and just ahead of that of Marcus Mariota of Tennessee. The bottom three in terms of ranking: Sam Darnold of the Jets, Josh Rosen of the Cardinals and Josh Allen of the Bills. The four rookies drafted in the first round are among the bottom five in passer rating.

Total QBR verifies their rankings. Mayfield is 29th, one spot ahead of Darnold, two ahead of Rosen and four ahead of Allen. Ryan Tannehill is 32nd, but the four rookies are in the last five in this assessment as well. (First in Total QBR: Second-year sensation Patrick Mahomes of Kansas City.)

None of this means a great deal about Mayfield's future or the Browns' belief in him. He has earned more time and trust with the way he practices, prepares, carries himself and plays.

The numbers show that Mayfield is struggling at times, but so are the other rookie QBs, and the numbers can't measure Mayfield's fire. Mike Ehrmann/Getty Images

His competitiveness will not show in any stat sheet, nor will his fire. Evidence: A few days after making it plain that he was not fast and was not brought to Cleveland to run, he broke free for a 35-yard scamper in Tampa. When the play ended with him taking a vicious shot to the head, Mayfield jumped up and got right in the face of the Bucs player who hit him.

That won't show up in a formula. Nor will other factors, such as the three rookies he has at receiver or bad officiating or missed blocks.

But other numbers show early trends, both positive and negative:

Mayfield's two touchdown passes against Tampa Bay put him on the positive side of the touchdown-to-interception ratio, but his 1.2 ratio (six touchdowns to five interceptions) is 24th in the league, according to ESPN Stats & Information.

Mayfield is completing 57.7 percent of his passes, which puts him 30th in the league. The next three? The rookies: Darnold, Rosen and Allen. One caveat with Mayfield's completion percentage: The Browns lead the league in dropped passes, many of them with Mayfield as the starter. David Njoku, Antonio Callaway and Rashard Higgins are all in the top 11 in percentage of passes dropped this season. If the Browns catch half of Mayfield's drops, he would be at or over 60 percent.

Mayfield's yards per attempt rank 26th in the league. That isn't great, but Mayfield's 6.9 yards per attempt are better than the marks of Dak Prescott, Mariota, Cam Newton and Joe Flacco. Mayfield's 12.0 yards per completion rank 12th in the league. The yards per attempt can improve, but both stats are impressive, given the nature of the Browns' receiving corps.

Mayfield has been sacked 18 times, ninth in the league. That number is too high. Coach Hue Jackson said Sunday that Mayfield is getting hit too much. TeamRankings.com reports that Mayfield has lost 115 yards on sacks, 10th-highest in the league. ProFootballReference.com states that Mayfield has an 8.8 percent sack rate, ninth-highest in the league. All of those numbers are too high on their own and are definitely too high given that Mayfield has made only four starts. How much of that falls on receivers not getting open is up for debate. The Browns designed a game plan for Sunday around him getting rid of the ball in a hurry; clearly, they are weary of seeing him take hits.

Finally, Mayfield's interception percentage is 3.2. That's very low, especially for a rookie. A year ago, DeShone Kizer was benched when his interception percentage reached 6.2. Mayfield's is almost half that and is 18th-lowest in the league. (As for interception percentage, Drew Brees is at 0.0 -- no interception in 220 attempts).

Among Mayfield's other stats, he's averaging 258 yards per game (22nd in the league). He's 1-3 as a starter, or 2-3 if his work in relief against the Jets is included. He has one fourth-quarter comeback and two game-winning drives -- against the Jets and Ravens,

Put it all together, and Mayfield is protecting the ball, but he's also holding the ball. He's getting the ball downfield, but when he does, either he isn't accurate enough or his receivers aren't catching it enough.

He has room to improve but provides assurance that he will get better the more he plays.

Mayfield can be better, but after four starts, he has shown enough to believe that he can and will be the team's quarterback on opening day in 2019.