While shortstop Brandon Crawford was at the All-Star Game, catcher Buster Posey was recovering from the cortisone shot he was to get in his left hip and the rest of the Giants were golfing, wine-tasting and checking in on Mickey Mouse during the break, the landscape of the National League West changed markedly.

When the Dodgers open the second half in Milwaukee, they will welcome beastly hitter Manny Machado to their lineup. When the Giants take the field at the Oakland Coliseum, in their ceaseless bid to prove they really are more than an 81-81 team, their biggest news will come from the training room.

Third baseman Evan Longoria , out since June 14 with a broken left hand, will begin his Triple-A rehab assignment Friday night for Sacramento in El Paso.

The Giants also should be able to reveal a better timetable for second baseman Joe Panik (groin strain) and, equally significant, decide after assessing pitcher Jeff Samardzija whether to ready him for Wednesday’s game in Seattle or shut him down long-term until they get a true handle on his shoulder and pectoral injuries.

On the field, the Giants have to cross their fingers Saturday night that pitcher Johnny Cueto , who went to Disneyland over the break, will continue to make progress in his third start back from a sprained elbow.

Cueto did not look like he was letting lose in either of the first two. Both lasted five innings, with his numbers in the second game against the Cubs on July 11 better than his return game six nights earlier against the Cardinals.

His runs and hits allowed improved from five and 10 against St. Louis to three and six against Chicago, while his strikeouts rose from two to seven. He gave up two homers in both.

“I thought he was a lot better today,” manager Bruce Bochy said after the extra-innings win against the Cubs. “It looks like he’s getting closer.”

It’s fitting, symbolically, that rookie Dereck Rodriguez will pitch the opener of the A’s series, as the Giants will have to rely on their younger players to try to catch the first-place Dodgers — now fortified with Machado — whether they add at the deadline or not.

Call these players the “92ers,” the year that Rodriguez, Andrew Suarez, Alen Hanson and Austin Slater were born. Steven Duggar, who is getting a long look in center field, can be an honorary little brother. He was born in 1993.

Rodriguez surveyed the clubhouse last weekend, with so many of his Sacramento buddies in big-league uniforms, and called it “awesome.”

“You start out with a group of guys and you see one by one they slowly start to trickle up,” he said. “You finally get up here and there are a bunch of the guys you started off with. It gives you that comfort level being with them most of the year.”

Bochy and his staff recognize that neither Rodriguez nor Suarez has pitched much beyond 150 innings in a season. Rodriguez is at 97, Suarez at 1121/3. While they will be asked to shoulder heavy responsibility down the stretch, Bochy said they will be monitored.

Farm report: Mac Williamson, who has slumped since his return to Triple-A, hit his first homer since June 26 on Wednesday in Fresno and added another in the third inning Thursday. … Chris Heston, continuing his recovery from a shoulder injury as he tries to get his career back on track, pitched four shutout innings with no walks and five strikeouts in his first game for Double-A Richmond, Va., on Sunday.

Henry Schulman is a San Francisco Chronicle staff writer. Email: hschulman@sfchronicle.com Twitter: @hankschulman