Colchester have signed Birmingham’s Denny Johnstone for an undisclosed fee and Brentford’s teenage midfielder Courtney Senior on a free transfer.
Johnstone, 21, made two substitute appearances after joining Blues in 2014, but was subsequently loaned to Macclesfield, Cheltenham, Burton and Scottish Championship Greenock Morton.
The former Celtic trainee scored 17 goals in 43 games for Morton last year.
Both he and Senior, 18, have signed two-year deals at the League Two club.
Senior made one first-team appearance for Brentford and also had a brief loan spell at Wycombe Wanderers.
Johnstone is Colchester’s third summer signing, following the acquisitions of ex-Southend defender Luke Prosser and Ben Wyatt from Maldon & Tiptree, and his transfer deal includes various add-ons.
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