Source: A.J. Cole to make Double-A debut Thursday night at Portland

Right-hander A.J. Cole, promoted from high Single-A Potomac to Double-A Harrisburg Tuesday, will make his Double-A debut Thursday at Portland against the Sea Dogs, according to a club source. Cole was 6-3 with a 4.25 ERA in 18 starts for Potomac. He has 102 strikeouts and 23 walks. In his last start July 20 against Lynchburg, Cole went six innings, allowed two hits, two runs, one earned run, one homer, one walk and struck out three batters. Cole has allowed only one earned run in his last nine innings of work. * I have been asked many times when right-hander Lucas Giolito, the Nationals' top prospect, will move up from rookie level. The Nationals like where Giolito is \and they will continue to have him start for the Gulf Coast League Nationals. They say he is making excellent progress, and are impressed with the makeup of the 19-year-old. A couple of times this season, Giolito has been pulled early in games when he allows a couple of hits or three or four walks in the same inning. The Nationals have a philosophy when dealing with Tommy John surgery rehabs that they monitor how many pitches are thrown per inning. If he throws a certain amount of pitches in the same inning, they will end his outing. It is not because they don't want Giolito to get shelled or worry about his mindset. They are instead following guidelines for protecting him from throwing too many pitches in one inning. Giolito has appeared in four games, tossed six innings and has a 0-0 record with a 3.00 ERA. He has allowed two earned runs, six walks and has struck out eight. The Nationals' new hitting coach, Rick Schu, last week was working as the hitting instructor with the Gulf Coast League Nationals, and said he watched video of Giolito hitting 98-99 mph with his fastball.