Ben Olsen (By Rob Carr — Getty Images)

D.C. United is close to finalizing a long-term contract extension for Coach Ben Olsen, whose squad is on pace for the greatest one-year recovery in MLS history.

According to sources familiar with the talks, the sides have tentatively agreed to terms after initiating negotiations in early July. Olsen, a former United midfielder and the longest-serving head coach in club history, is in the final year of his pact. Financial information for MLS coaches are generally confidential, and the level of Olsen’s pay raise and number of years involved are unclear.

Olsen, the leading candidate for MLS’s coach of the year award, declined comment. United officials said they do not comment on negotiations involving personnel.

A year after setting the league record for fewest victories (three), United sits atop the Eastern Conference and is third overall in the 19-team league with a 14-8-4 record and 46 points.

The club has enjoyed a 30-point surge and, with four wins in the last eight regular season matches, would set the MLS mark for best improvement in consecutive years based on point increase and points per game. From 1999 to 2000, New York rose 39 points over 32-game seasons. (MLS teams now play 34-game schedules.)

Olsen, 37, is the second-youngest head coach in MLS, two years older than Jim Curtin, the Philadelphia Union’s interim boss.

Olsen is in his fourth full season at United’s helm and has held the top position since August 2010, when he was upgraded from an assistant’s job to replace Curt Onalfo. He guided the team to the 2012 Eastern Conference finals but finished with a 3-24-7 record last year. The club did, however, win the U.S. Open Cup for the third time, securing a berth in international competition this year.

In the offseason, without the budgetary muscle to match expensive signings by other teams, Olsen and General Manager Dave Kasper overhauled the roster by acquiring several league veterans and mixing them with rising young players. It was then Olsen’s job to build chemistry and forge a new direction. After a 0-2-1 start, United has gone 14-6-3 and lost once at RFK Stadium. With a re-built backline in front of maturing goalkeeper Bill Hamid, United has conceded the third-fewest goals in MLS (30) and posted nine shutouts.

D.C., which leads Sporting Kansas City by four points in the conference, will visit the Vancouver Whitecaps (7-6-12) on Saturday night and the New York Red Bulls (7-8-10) next Wednesday.

United’s head coaching history

Bruce Arena: 1996-98

Thomas Rongen: 1999-2001

Ray Hudson: 2002-03

Peter Nowak: 2004-06

Tom Soehn: 2007-09

Curt Onalfo: 2010

Ben Olsen: 2010-present