SAN FRANCISCO -- Sam Dyson, the newest Giant, expressed belief that simplifying his pitching approach will help him regain his effectiveness.
Dyson, the right-hander whom San Francisco acquired Tuesday from the Texas Rangers for a player to be named, officially joined the Giants on Friday and threw off a bullpen mound for manager Bruce Bochy and pitching coach Dave Righetti.
Relying on a power sinker, Dyson converted 38 saves in 43 opportunities for the Rangers last year. However, he was 1-6 with a 10.80 ERA and four blown saves in 17 appearances this season when the Rangers designated him for assignment June 2. The Giants obtained him four days later.
The difference, Dyson said, is "just getting back to the basics, using the sinker, stop trying to reinvent stuff to get guys out and don't second-guess the reason I'm here."
Bochy said Dyson, 29, was available to pitch Friday night, though the Giants would try to avoid using him in the Interleague series opener against the Minnesota Twins due to his bullpen stint.
To clear room on the 25-man roster for Dyson, the Giants optioned utility man Orlando Calixte to Triple-A Sacramento. Recalled on May 30 when outfielder Mac Williamson was sent to Sacramento, Calixte batted .160 (4-for-25) in eight games. Calixte started six games in left field and one in right for the Giants, who have used 12 left fielders this season.
Calixte, 25, valued his stint with the Giants.
"It has been an unforgettable experience," he said. "I learned a lot from the veterans. They gave me a lot of advice."
Bumgarner throws in 'pen
Left-hander Madison Bumgarner tossed 20 fastballs in the Giants' bullpen Friday, his first throwing session off a mound since his April 20 dirt-bike accident.

Bochy said Bumgarner will throw twice more in the bullpen before pitching a simulated game during the Giants' June 15-18 visit to Denver.
Though the Giants' timetable for Bumgarner's return is not definite, he could return to the starting rotation after the mid-July All-Star break, according to most estimates.