INDIAN WELLS, Calif. (AP) — In between trade talks and early negotiations with free agents, baseball general managers considered some wide-ranging changes that include broader use of instant replay by umpires, changed roster limits for September and protective headgear for pitchers.

On the first day of the GM’s three-day annual session, the New York Mets announced Wednesday they had reached an agreement to terminate outfielder Jason Bay’s contract with one guaranteed season remaining. The Los Angeles Dodgers finalized a deal to hire Mark McGwire to be their first base coach.

Arizona general manager Kevin Towers said he’d listen to trade offers for two-time All-Star right fielder Justin Upton but thought a swap was not likely. And Texas GM Jon Daniels said the Rangers remained interested in re-signing All-Star slugger Josh Hamilton.

At their first meeting since a pair of pitchers were hit on the head by line drives, baseball general managers discussed ways to protect hurlers from injuries in the future.

Major League Baseball staff have said a cap liner with Kevlar, the high-impact material used by military, law enforcement and NFL players for body armor, is among the ideas under consideration.

“If we settle on something that is going to make sense, and obviously the pitcher has to be comfortable with it, we’ll obviously put that in as soon as possible,” MLB executive vice president Joe Torre said Wednesday.

Walt Weiss has been hired to replace Jim Tracy as manager of the Colorado Rockies.

The team made the announcement late Wednesday night after owner Dick Monfort and top officials deliberated at the general managers’ meetings — held at a hotel Monfort owns.

Weiss, the 1988 AL Rookie of the Year, and Arizona coach Matt Williams were thought to be the favorites to replace Tracy, who quit Oct. 7 following a last-place finish in the NL West. Rockies bench coach Tom Runnells and first baseman Jason Giambi also interviewed.