ARLINGTON — It’s Fien Time.

The Texas Rangers officially signed first-round draft pick Gavin Fien, the No. 12 overall selection, the club announced Monday night. The team officially announced agreements with right-handed pitcher Mason McConnaughey (fourth round), left-handed pitcher Ben Abeldt (fifth round) and right-handed pitcher Julius Sanchez (18th round).

The Rangers signed Fien to a $4.8 million bonus, a person with direct knowledge of the negotiations told The Dallas Morning News. That figure is a significant under-slot bonus; the designated slot value for the 12th overall selection this year was north of $5.7 million. Jim Callis of MLB.com was the first to report the financials.

Fien, whom the Rangers selected 12th overall in last Sunday’s MLB draft, is already listed as the club’s fourth-best prospect according to Baseball America’s updated rankings. He’s the second-ranked position player prospect behind only shortstop Sebastian Walcott.

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The 18-year-old, who had initially signed to play college baseball at Texas, was among a number of highly-touted high school middle infielders and last week’s draft and was the No. 22 prospect in MLB Pipeline’s big board beforehand. The 6-foot-3 infielder starred for the Team USA 18-U national team last summer with a 1.109 OPS in eight games at first base. The Rangers plan to start him at shortstop.

“This is a guy with plus power and a plus hit tool,” Rangers senior director of scouting Kip Fagg said shortly after Fien was picked. “We’re excited about the offensive potential and the defensive player. This is a legit hit/power combo.”

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