Steve Birnbaum (U.S. Soccer)

Maccabi Tel Aviv has increased its offer for D.C. United defender Steve Birnbaum to $1.5 million, the Insider has learned, but the timing does not make much sense for the MLS club.

By selling now, United would only be able to collect half of the fee. (The balance goes to MLS, which owns all player contracts.) However, the club’s share would rise to two-thirds — in this case, $1 million — if United waited until this winter when Birnbaum has completed three full seasons.

The MLS transfer-fee scale is: one-third for a player with one year of MLS experience; half for two years; and two-thirds for three seasons or more. (The sale of a homegrown player, at any point, yields three-quarters of the sale price.)

Maccabi, Israel’s most decorated club, finished second in the top division last season and is vying for slot in the UEFA Europa League. The second leg in the third qualifying round is Thursday against Romanian side Pandurii.

Birnbaum, the No. 2 overall draft pick in 2014, will turn 26 in January. This summer, he was a member of the U.S. national team at Copa America Centenario and an MLS all-star.

This spring, when Maccabi showed interest in Birnbaum, the club was offering around $700,000.

Birnbaum is under contract with United and MLS until the end of the 2017 season. Given his success for club and country, he is well-positioned to renegotiate his contract in the near future. This year, he is due to earn $116,350, the 15th-highest total on the 30-player roster.

Whether Israel is the right place for Birnbaum is another issue; the level of play is not as high as in many European countries.

Because of his Jewish heritage, Birnbaum would not count against Maccabi’s foreign player limit.

Meantime, United (5-8-8) is weighing trade opportunities before MLS’s transfer and trade window closes at midnight Central time Wednesday. The club’s international search is not expected to yield any signings.

D.C. — which is second to last in the 20-team league in scoring with 20 goals in 21 matches — has acquired three attacking players via trade this summer: Lloyd Sam (New York Red Bulls), Patrick Mullins (New York City FC) and Kennedy Igboananike (Chicago Fire). It also dealt forward Fabian Espindola to Vancouver for allocation money. In the final year of his MLS contract, Espindola declined to report, prompting the Whitecaps to sell him to Mexican club Necaxa.

This week’s MLS deadline applies to international transfers and trades only. Clubs may continue to pursue free agents and players from the lower domestic leagues until the Sept. 15 roster freeze. Trades not involving players are also allowed.