ADELANTO —— Storm left-hander Sean Thompson, the team's most effective starter this season, was promoted to Double-A Mobile (Ala.) on Monday as the team shook up its pitching staff.

Edgar Huerta, who had been the only lefty in the Lake Elsinore bullpen, was loaned to a team in the Mexican Summer League.

"It's well-deserved," manager Rick Renteria said about Thompson's move.

The 22-year-old went 4-1 with a 2.16 ERA in six starts with Lake Elsinore.

In 33 1/3 innings, he struck out 45 batters and walked just 13. In three previous seasons in the Padres organization, Thompson went 20-10 with a 3.07 ERA while striking out 323 batters and walking 134 in 284 1/3 innings.

Huerta was largely ineffective this season. He was 1-0, but had a 10.95 ERA in eight appearances. Between four separate trips to the disabled list because of a hip strain last season, the reliever compiled a 1-2 record and a 4.91 ERA in 12 appearances for Triple-A Portland (Ore.) and Mobile.

Clark Girardeau and Ryan Trytten, both of whom were at Low-A Fort Wayne (Ind.), will replace Thompson and Huerta on the Storm roster.

Trytten was signed as a minor league free agent in December after spending last year pitching for Lincoln, Neb. of the independent Northern League. In 10 relief appearances for the Wizards, the 24-year-old right-hander compiled a 1-0 record with a 1.20 ERA.

He will initially be used in middle relief, Storm pitching coach Dave Rajsich said.

Girardeau will be in his second stint with the Storm. Last year, he went 3-2 with a 4.53 in 12 games (nine starts) for Lake Elsinore. This season, the right-hander was 1-1 with a 4.15 ERA in six starts for Fort Wayne.

Renteria said Girardeau is a candidate to fill Thompson's spot in the rotation.

Big hole

The Storm came into their series in High Desert having lost three straight games for the first time all season after being swept by Lancaster at The Diamond during the weekend, and part of the problem could be the absence of a big bat in the middle of the lineup.

The losing streak coincided with Michael Johnson's stint on the disabled list. The slugging first baseman went on the DL before Friday's game because of inflammation in his right hand.

Johnson said he couldn't point to one incident that caused the injury.

"It started up a couple of weeks ago," Johnson said. "It's just one of those things that came up. It was there. I could feel it on my swings, but I don't know how much it was really affecting it." Johnson received a cortisone shot Friday and said he should be able to play when he's eligible later this week.

"It's feeling really good right now," Johnson said. "I'm just waiting for the cortisone to do its work. That's the only thing you can do.

"It should be good to go Wednesday or Thursday this week."