Flores, 46, spent the last five seasons as a field coordinator in the Chicago Cubs' minor-league system.
The outfielder must spend the entire season on Texas' 25-man roster or be offered back to the Phillies.
The Phillies think the third baseman can solve his struggles by hitting the ball into the air more often.
With Tommy Hunter and Pat Neshek aboard, the Phillies will build their bullpen around the two veterans and 28-year-old Hector Neris.
He would join Pat Neshek, who agreed to a two-year earlier this week.
Get the latest breaking news and rumors here as free agency begins in Major League Baseball.
The Phils manager does not believe in having rules, but "not having rules doesn't mean not having expectations."
The Phillies have operated this offseason on the principle that there is not one move - or two or three moves - that can morph them into contenders in 2018.
The Phillies and Orioles have not discussed a Machado trade this offseason, according to a source. Machado, 25, is a free agent after the 2018 season.
LAKE BUENA VISTA, Fla. (AP) - Fittingly, Jack Morris reached the Hall of Fame in extra innings.
The righthander is a junior pitcher/outfielder at Calvary Christian High in Florida.
The Phillies could wait for the perfect deal for Cesar Hernandez or Freddy Galvis - a deal that may not materialize - at the risk of sacrificing whatever value their current infield surplus has.
Get the latest breaking news, rumors and trade buzz here from Major League Baseball's winter meetings at Disney World in Orlando, Florida.