After 11 losses in 16 games, they have to be wondering if they gave up on the young right-hander too soon.O'Sullivan hasn't won in three starts with Kansas City, and the 22-year-old figures to be highly motivated to beat his former club as the Royals visit the Angels to begin a three-game series Monday night.Los Angeles (56-57) was within striking distance of first-place Texas when it visited the Rangers on July 22, the same day it struck a deal to acquire third baseman Alberto Callaspo from Kansas City (47-64) for O'Sullivan (1-2, 4.30 ERA)."This wasn't by any means an easy decision on (general manager Tony Reagins') part," manager Mike Scioscia said. "But to get something, you have to give something up. Sean is a young kid, not even 23 yet. He has a bright future. We think it's a trade that will help both organizations."Callaspo has hit .291 with the Angels -- the team that originally signed him in 2001 -- while giving them an option other than Maicer Izturis or the struggling Brandon Wood, but he's only driven in five runs. Los Angeles is 5-11 since the trade and sits nine back of Texas after Sunday's 9-4 loss in Detroit.O'Sullivan fell to 0-2 with a 6.06 ERA with the Royals after giving up four runs over 5 1/3 innings in a 4-3 loss at Oakland on Wednesday.Yet for a pitching staff that's on its way to having one of the majors' five-worst ERAs (5.04) for a second straight season, Kansas City is happy to have another promising young arm."The first thing I asked Scioscia when I was traded was, 'Hey, am I going somewhere where they wanted me? Were they asking for me?'" O'Sullivan told MLB's official website. "And he told me yes. I just want to be somewhere where they want me to pitch, where I'm going to get a chance to establish myself at this level and help this team win."O'Sullivan's mound opponent is Ervin Santana, whose injury in June 2009 led to him making his major league debut.Santana (10-8, 4.11) can only wish he missed his most recent start. The right-hander surrendered nine runs and 12 hits in 3 2/3 innings in a 9-7 loss at Baltimore on Wednesday."Nothing I can do, just forget about this one and get to the next one," Santana told the Angels' official website. "I had good stuff in the bullpen. I'm just going to leave this in this ballpark and get to the next (game)."Santana is 4-4 with a 4.47 ERA in nine starts against the Royals.He might have a good shot at bouncing back from last week's dreadful outing. The Royals lost 3-2 in Seattle on Sunday to fall to 2-4 on their road trip, in which they've totaled 11 runs while hitting .198."Sometimes you go through times like this," designated hitter Brayan Pena told the Royals' official website. "We're putting the ball in play, and I think we're going to do better and, hopefully, in the Angels series we're going to score some runs."Kansas City won two of three last month in Anaheim despite being outscored 13-6.