Jeffrey, a 23-year-old Texas native, will become eligible when the international transfer window opens next week. United claimed him in an MLS waiver draft. Contract terms were not disclosed.
He was the 2008 Parade high school player of the year before signing with Belgian club Brugge. He captained the U.S. under-17 national team and performed for both the under-20 and under-23 squads. In a failed Olympic qualifying bid by the U-23s last year, he played alongside United’s Perry Kitchen and Bill Hamid.
“He is a technically gifted midfielder who has solid experience at various U.S. youth national team levels and recently with Mainz,” United General Manager Dave Kasper said in a written statement.
Jeffrey started 79 matches for Mainz’s reserves, who compete in a German regional league (fourth tier).
Jeffrey was exposed to the waiver draft because no club wanted to lose its place in the allocation order in order to select him, the league said. (When a team utilizes a pick in the allocation draft, it drops to the back of the pack.)
Clarification: Jeffrey was available in a special weighted lottery, not through the allocation order. No other teams were willing to enter the lottery, so United was able to claim him through waivers. (When a team wins a lottery, they are not eligible for any further lotteries during that particular season.)
In other news, Coach Ben Olsen was fined $2,000 by MLS for derogatory comments about referee Matthew Foerster following Saturday’s 1-0 loss to the Vancouver Whitecaps.