LEADING OFF: All-Star arms, Nola’s debut, Who’s on first?

A look at what’s happening all around the major leagues today:


National League All-Stars Gerrit Cole and Michael Wacha are both on the mound in interleague games. Cole (13-3) pitches for Pittsburgh against Kansas City lefty Jason Vargas (5-2), set to come off the disabled list. Wacha (10-3) starts for St. Louis against Chicago White Sox rookie Carlos Rodon (3-2).


Prized pitching prospect Aaron Nola makes his major league debut for Philadelphia against Tampa Bay. The 22-year-old righty was selected seventh overall last season out of LSU and will become the first Phillies player since Pat Combs in 1989 to debut in the majors the year after getting drafted. Nola was a combined 10-4 with a 2.39 ERA in 18 starts between Double-A Reading and Triple-A Lehigh Valley.


The Cardinals are expected to call up top prospect Steve Piscotty for their interleague series against the White Sox. Drafted 36th overall in 2012, Piscotty has been working to convert from outfield to first base. He was batting .272 with 11 homers and 41 RBIs at Triple-A Memphis.


Help could be on the way for Atlanta’s sagging offense. First baseman Freddie Freeman, out since June 18 with a bruised right wrist, might begin a rehab stint as early as today. Freeman was upbeat after playing catch and taking swings before Monday night’s game against the Dodgers. ”He’s trying to talk me into putting him into the lineup tonight,” Braves manager Fredi Gonzalez said.


NL Rookie of the Year Jacob deGrom (9-6, 2.14 ERA) makes his first appearance since his terrific All-Star outing – three strikeouts on 10 pitches. He’ll try to lead the second-place New York Mets past the NL East-leading Nationals, a team he’s never beaten. In three career starts against Washington, deGrom is 0-2 with a 4.15 ERA. The Nationals plan to call up right-hander Joe Ross (2-1, 2.66) for his fourth start in the majors.


Playing in a National League park has left Texas without a designated hitter against Colorado. Prince Fielder, who has spent most of the year at DH, started at first base Monday over Mitch Moreland, but manager Jeff Banister said he’ll give both players a rest during the three-game series. ”Prince playing in the All-Star Game and going through the home run contest, he does need a day somewhere also,” Banister said.


Todd Frazier tries to build upon his first hit since winning the All-Star Game’s Home Run Derby at Great American Ball Park. The Reds’ third baseman went 0 for 3 in the All-Star Game, and then was 0 for 10 during a weekend series against the Indians. He broke out with a homer in the first inning Monday off Cubs pitcher Clayton Richard. Frazier hasn’t homered in back-to-back games since June 16-17.