The first wisps of fall are creeping into New England. Temperatures in Boston struggled to reach the 70s on Monday as the Red Sox took the field to open their final homestand of the season.

There isn’t much left to prove for the 2015 Red Sox as they play out the string and try to avoid finishing in last place for the third time in four years.

But unlike the other last-place finishes, there has been optimism surround the team for the past month. The Sox began the week having won 10 of 15 games. They have a 27-19 record since July 30.

The recent improvement is due in large part because of the inspired and energetic play of a core of young players: Xander Bogaerts, Mookie Betts, Blake Swihart, Jackie Bradley, Jr. and Travis Shaw are all under the age of 26. All have proven they have a future in the big leagues.

The challenge facing Dave Dombrowski, Boston’s new president of baseball operations, is how to mold that core into a team that will contend for a playoff berth in 2016. And, despite the recent success these young players have shown, there is work to do.

It all begins with the pitching staff.

Is the starting rotation good enough to stand pat for next year? That question was laughable just a few weeks ago, but improved performances by Rick Porcello, Wade Miley and Joe Kelly (before he was shut down for the season) have given us reason to reconsider the premise that the staff must be ripped up and rebuilt from scratch.

The makings of a rotation are there, but this success doesn’t mask the fact that the team still needs to add an ace.

The easiest way to do that is to sign a free agent, and there are plenty on the market. It’s also the riskiest way. David Price, Johnny Cueto or Jordan Zimmerman will come at a premium, commanding the type of contract that would help a team now but leave them on the hook for tens of millions of dollars in six or seven years.

If the Sox can’t sign one of the top available arms through free agency, they would have to find one via trade.

That won’t be easy, and would probably mean breaking up the core of young players we already listed.

Clay Buchholz has also shown he has the talent to be a top-of-the-rotation pitcher, but he’s never been able to make it through an entire season without landing on the disabled list. The team has a $13 million option for next season. That’s middle-of-the-rotation money, and the Sox will probably pick it up.

It doesn’t change the fact they need an ace.

The Sox also need a bullpen. That needs to be built from scratch.

Boston’s relievers sport a 4.36 ERA, third-worst in the American League. There are very few pitchers in the bullpen that can be depended on.

Closer Koji Uehara’s season ended early because of a broken wrist and he won’t throw again until after the season. He’ll be 41 when next season begins. Can you automatically assume he will return to form?

There are relief options on the free-agent market.

Tyler Clippard, Tony Sipp and Darren O’Day could all help the renovation project, but bullpens are tricky things to construct. Dombrowski had trouble doing it in Detroit and his predecessors had inconsistent results in Boston.

Inconsistency is what the Sox need to avoid beginning next season. The team’s play over the past month has been nice, but it shouldn’t overshadow the fact that there is still significant work to be done to get this team back on track.

Tom Caron is a studio host for the Red Sox broadcast on NESN. His column appears in the Portland Press Herald on Tuesdays.