Todd Bowles celebrates his 54th birthday on Saturday and will be back in the office Monday morning, coming off a bye week, to begin the homestretch -- six pivotal games that probably will determine if he's coaching the New York Jets when he's 55.

Bowles is 19-23, with no playoff appearances. It's not the kind of résumé that screams, "Contract extension!" In this case, there are mitigating circumstances. This is Year 1 of a major rebuild, with ownership on record as saying he won't be judged by wins and losses. Johnson & Johnson -- brothers Woody and Christopher -- want to end the season with a good vibe about the team, feeling optimistic about the future.

Last week's lackluster loss was a hiccup, no doubt, but acting owner Christopher Johnson has told people he's encouraged by the direction. In September, he told reporters, "I think it’s going to be obvious to all if this team is progressing." So far, yes, the Jets (4-6) are ahead of where many experts expected -- read: in contention for the No. 1 pick in the 2018 draft -- but they're about to embark on a brutally tough stretch run.

The Jets face four of the top 10 teams in ESPN's latest power rankings -- the Carolina Panthers (10th), Kansas City Chiefs (fifth), New Orleans Saints (third) and New England Patriots (second). The Jets are projected to finish with 5.4 wins, according to ESPN analytics.

If Bowles gets this team to six wins, he'd absolutely deserve to return with a contract extension (he's signed through 2018 and ownership won't make him coach as a lame duck). A 6-10 mark would constitute progress on every level, especially when you consider last season's 5-11 record. You could make the argument he's already done enough, but ownership will make its decision based on the full 16.

Beyond wins and losses, there are a few key areas in which progress can be measured over the next six weeks:

Competitiveness: This is critical. Blowouts won't be tolerated. So far, so good. Their past four losses were decided by seven points or fewer, an indication they're hanging tough against superior teams. (The loss in Tampa was the outlier.) In 10 games, the Jets have trailed by more than one possession for only 47 minutes, much of that coming in the Week 2 loss to the Oakland Raiders. But now comes the tough part, as they face some of the hottest teams in the league.

Problem solving: The mark of a good coaching staff is its ability to fix things on the fly. Example: Remember the Patriots' porous defense in the beginning of the year? You don't hear much about that anymore, do you?

The Jets have made a similar improvement with their run defense, which went from 143 yards per game (first five games) to 93 (past five). But they still have a couple of leaks that need to be plugged. The rushing offense has declined (111 yards to 92) and the penalties -- oh, the penalties. It has been a season-long issue, and it needs to change because it's a bad look.

Player development: Veterans such as Josh McCown, Demario Davis, Austin Seferian-Jenkins and Jermaine Kearse are having career years, statistically. At the same time, Jamal Adams, Marcus Maye, Darron Lee, Robby Anderson and Jordan Jenkins have established a young core. This illustrates that Bowles, who showed in 2015 he can coach an old team (10-6), is capable of developing young talent. It hasn't happened at quarterback, but that can't be pinned on coaching.

You'd like to see more from the young players over the final six games. Because of injuries, rookies Chad Hansen, ArDarius Stewart and Elijah McGuire will be asked to contribute off the bench. Can they make an impact? And what about Rashard Robinson, whom they acquired at the trade deadline? The personnel department loves his upside, but he has yet to play a down on defense.

Team chemistry: They just have to keep doing what they're doing. Or let's put it another way: Don't be the 2016 Jets or the 2017 New York Giants.