FOXBOROUGH, Mass. -- Over the past three weeks, the reminders have been plentiful about how fast things can change in the NFL.
Patriots tight end Benjamin Watson appeared to be fighting for a roster spot in the final preseason game, only to become one of the team's heroes with two late touchdown grabs in the season opener.
In that game, the Patriots looked like they were headed for a loss, trailing 24-13 with 5:25 remaining in regulation, only to charge back for a dramatic win.
Then there was this Sunday's 16-9 loss to the Jets. The Patriots had controlled much of the first-half action, leading 9-3, when -- poof! -- the Jets charged out of the locker room, scored in just three plays on their opening drive and never looked back.
Such sudden shifts can create a roller coaster of emotions, but the teams that weather them and keep an even keel usually have the best chance to succeed.
With this in mind, here is a look at the current Patriots seesaw -- with some areas that are reason for concern, and others that still yield optimism:
Top areas of concern
1. Tom Brady's comfort level: Maybe the expectations were too high, with the idea that Brady was medically cleared for action and thus would pick up where he left off in his record-setting 2007 campaign. His remarkable season-opening comeback might have only heightened those expectations.
Most notable Sunday against the Jets was Brady's spotty accuracy and his delay-of-game penalties, which reflected a player still growing comfortable with game speed and grasping all the challenging aspects of managing a game. This isn't like riding a bike; apparently you don't just hop on and start pedaling again.
A 63 percent passer over his career, Brady connected on just 48.9 percent of his throws, some of which weren't dictated by pressure. Other deliveries, like his interception, were a result of hurrying himself because of an oncoming rusher.
"I think it has to do with poor technique," Brady said Monday during his regularly scheduled radio appearance on sports radio WEEI. "Sometimes my technique hasn't been what I've hoped it to be the last two weeks. I have to improve on that. I always feel being an accurate passer is like a good golf swing. If you do it right, it's going to go where you want it. I have to be more accurate throwing the football."
2. Health of key players: It's only Week 2 of the season and the Patriots were already without their leading receiver (Wes Welker, knee injury) and leading tackler (Jerod Mayo, right MCL). The injuries have tested the Patriots' depth -- Julian Edelman filling in for Welker and Gary Guyton for Mayo.
The loss of Mayo and fellow rookie Tyrone McKenzie (torn ACL), in particular, is handcuffing the team's ability to scheme, because of a linebacker shortage. The Patriots were locked into a four-man line Sunday because of the situation. They need more consistent pressure out of the defensive line.
3. Void with defensive playmakers: When the Patriots needed to make a play in each of the past two games -- on Buffalo's long fourth-quarter drive, and on third-and-13 late in the third quarter against the Jets -- they couldn't deliver.
Would things have been different if Richard Seymour and Mike Vrabel were on the field?
The answer to that question is subject to debate, based on the defense's subpar performance in 2008. At the least, the Patriots have to be a bit concerned that some of the same problems from last season -- lack of a pass rush, third-down-and-long struggles -- have continued to crop up.
4. Where is the running game? After finishing seventh in the NFL last season in rushing average (4.4 yards per carry), the Patriots have shied away from pounding the ball through two games. They have 43 carries for 156 yards (3.6 avg.).
On top of those numbers, most troubling has been the inability to pick up 1 yard on fourth-and-1 (versus Buffalo) and third-and-1 (versus New York). That is an indication of a team's losing the physical battle at the line of scrimmage.
The running game looked like it was picking up some momentum in the third quarter against the Jets, but the Pats knocked themselves out of it with their own miscues.
Top reasons to alleviate concerns
1. The offense has moved the ball: While the offense hasn't produced the desired point total, it's not like it has been stuck in neutral -- 441 yards against the Bills, and 299 against the Jets. The red zone, along with short-yardage critical situations, has been the primary nemesis.
The Patriots were 0-for-3 converting touchdowns in the red zone against the Jets, and 3-of-5 against the Bills.
Receiver Randy Moss needs to become more involved in this critical area of the field.
2. Penalty pace isn't likely to continue: The Patriots set an NFL record for fewest accepted penalties in a 16-game season last year, with just 57.
Through two games this season, they've been flagged for 17, putting them on pace for 136. Some infractions, such as Brady's two delay-of-game penalties, are rare for an entire season, let alone one game.
Furthermore, after an airtight performance on special teams in the season opener, the ship sprung some leaks against the Jets. Special-teams captain Sam Aiken was penalized twice, a sign of a complete breakdown.
While it's a projection that the Patriots won't continue down the same penalty path, it is hard to imagine that the club will be as undisciplined as it has been to this point. The high total under Bill Belichick was 111, which came in the 2003 Super Bowl season.
3. The Brady-Moss connection is still in town: There have been flashes over the past month of Brady and Moss rekindling their magic from 2007, namely in the third preseason game against the Redskins and in the season opener against the Bills when Moss had 12 receptions for 141 yards.
Against the Jets, Moss was blanketed by cornerback Darrelle Revis, and Revis was the knockout winner on most scorecards. Although Moss said the Jets rolled safety help over the top to take him out of the game, it didn't seem that was a primary part of their game plan.
But one game shouldn't overshadow the signs that were previously spotted.
When Brady and Moss decide to dial it up, they remain one of the NFL's most lethal combinations, and that alone makes the Patriots dangerous.
4. Coaching staff will maximize talents: Even with the bitter aftertaste of the loss to the Jets -- in which the decision to put the game in Brady's hands could be questioned based on his comfort level -- Bill Belichick and his staff haven't all of a sudden lost their touch overnight.
They remain one of the top staffs in the ultracompetitive NFL.
With a challenging two-game stretch ahead with home games against Atlanta (2-0) and Baltimore (2-0), they'll need to come up with top plans -- and find a way for the team to win the critical situations that decide games -- so the Patriots don't dig themselves too big a hole.
As recent history has shown, this time of year is generally about putting up enough wins to stay in the chase, and positioning the team to play its best football down the stretch.