New York ? As baseball moved within two days of another work stoppage, commissioner Bud Selig arrived at major league offices and negotiators worked late into the night to try to avert a strike.

Players are set to walk out Friday unless there is an agreement for a labor contract. Because of the threat, five of the 12 teams traveling for weekend series pushed back their flights a day, waiting to see if compromises could be reached on the main sticking points: levels for a luxury tax and revenue sharing.

“The same issues are unresolved,” Selig said late Wednesday night. “It’s been very constructive. Both sides are reaching out, but I can’t tell you we’re any closer. Only time will tell.”

Selig, who presided over the 1994-95 strike that led to the first cancellation of the World Series in 90 years, did not personally participate in the day’s five negotiating sessions, which mostly were brief. The last talks ended just past midnight, and bargaining was to resume today.

“The length of the meeting doesn’t always indicate whether it was a good meeting or not,” said union lawyer Steve Fehr, the brother of union head Donald Fehr.

Selig appeared briefly at the fourth meeting, only to say “Hello,” union lawyer Michael Weiner said.

“I still think we’re going to get something done,” said Atlanta pitcher Tom Glavine, the NL player representative. “I just think we’re all too close on too much of this to let it fall apart.”

Owners want to slow spending by high-payroll teams with a luxury tax and in their last formal proposal wanted to increase the amount of locally generated revenue that teams share from 20 percent to 36 percent. Players are at 33.3 percent and want to phase in the increase.

While negotiators didn’t disclose details, management increased its proposed threshold for the luxury tax by $5 million to $112 million and the union dropped by $5 million to $120 million, Boston player representative Johnny Damon said. The sides were still discussing all the proposed rates and thresholds, and the union didn’t want a tax in the final year.

The sides also discussed contract language that dealt with the owners’ desire to fold two franchises, one general manager said on condition of anonymity. The union has opposed contraction.

Pressure on the negotiators increased with each passing hour as they tried to prevent the sport’s ninth work stoppage since 1972. The first game affected would be at Chicago’s Wrigley Field, where the Cubs are to play the Cardinals at 2:20 p.m. Friday.

“No there is not going to be any extension,” Toronto player representative Vernon Wells said. “We set a date, we’ll stick by it and, hopefully, something will get done before then.”

Since the union set the strike date Aug. 16, fans have expressed anger and frustration. A sign in the right-field bleachers at Chicago’s Comiskey Park on Wednesday read: “On Strike/Who Cares/Go Bears.”

“We see the signs, and you hear comments from time to time about strike-related stuff. Sometimes those things are harsh,” the Brewers’ Mark Loretta. “It’s so hard to try to explain to people what the issues are when you’re talking about those kinds of dollars and this kind of industry, and the fans are in the middle of it.”

Just in case there is a strike, some Cleveland players gave the clubhouse attendants their season-ending tips Wednesday, and Tim Wakefield and Ugueth Urbina of Boston packed their belongings into boxes after a 7-0 loss to the New York Yankees at Fenway Park. The White Sox, also off today, might have ended their season with Wednesday’s 8-0 win over Toronto.