SAN DIEGO -- Before this week started, the San Diego Padres were looking forward to their next seven games with high hopes.
In back-to-back series, the team with the third-worst record in the National League would be hosting the team with the second-worst record (Miami) and the team with the worst record (Cincinnati).
So far, so good.
The Padres wrapped their four-game set with the Marlins by winning the last three games to end May with a winning record (15-13) after getting an 8-3 win on Thursday.
Now the Padres (25-33) seek to win a fourth straight game for the first time this season in the opener of a three-game set with the Cincinnati Reds (20-37) at Petco Park.
But Friday arrives with a twist.
Right-hander Walker Lockett, who has struggled at Triple-A El Paso this season, will make his major league debut with the Padres. He will be facing Reds' right-hander Tyler Mahle, who is 3-6 with a 4.76 ERA in his second major league season. Mahle has never faced San Diego.
Lockett, the Padres' fourth-round pick in the 2012 draft who turned 24 on May 3, was 2-5 with a 5.31 ERA in 10 starts in the Pacific Coast League when he got the call from the Padres.
Lockett is filling the void left when rookie left-hander Joey Lucchesi went on the disabled list May 15 with a hip strain. It is unclear when Lucchesi will return.
Relievers Robbie Erlin and Matt Straham filled the first two starts Lucchesi missed. But Padres manager Andy Green prefers to keep both in the bullpen.
"In regards to Robbie, I don't want to say that ship has sailed because potentially we could come back to him to start at some point in time," said Green of the left-hander who has been brilliant out of the bullpen but has given up 12 runs (11 earned) in seven innings over two starts.
"But he's pitched so good out of the bullpen ... he's been so valuable in saving arms and preserving guys that we like him in that role."
So the Padres turned to Lockett, who seemed on line to an earlier major league debut before suffering a lower back strain while with El Paso exactly a year ago.
"We're excited about giving Walker the opportunity and watching him run with it," Green said. "He's had outings in Triple-A that have been good. His numbers are not great right now with El Paso but this is the time when you start taking looks at guys and he has the opportunity to come up here and establish himself and possibly earn another shot the next time around.
"Walker's performance is better than the numbers are, which you hear in the Pacific Coast League quite often for pitchers at El Paso. It's a very tough pitching environment. It's a four-pitch mix arsenal ... it's 92-95 ... he's not light in the stuff department."
Neither is the 23-year-old Mahle, who leads all major league pitchers 23-or-young with 56 strikeouts.
Mahle will be making his 12th start of the season and 16th start of his career.
He has allowed 32 runs (31 earned) on 61 hits and 22 walks in 58 2/3 innings. Opposing hitters are batting .270 against Mahle, who has a 1.41 WHIP after allowing four runs on six hits over five innings during a no-decision in Cinncinati's 6-5 win at Colorado Saturday.
