Here is a paragraph from the Article,
Jackie Robinson: Baseball’s Noble Experiment, By William Kashatus...
"Those efforts helped the Dodgers to capture a pennant,
and on September 23, jubilant Brooklyn fans cheered their first baseman with a “Jackie Robinson Day” at Ebbets Field. In addition to a new car and other gifts, Robinson received tributes for his contribution to racial equality. Song-and-dance man Bill “Bojangles” Robinson, one of the guest speakers, told the crowd: “I’m 69 years old but never thought I’d live to see the day when I’d stand face-to-face with Ty Cobb in Technicolor.”
That paragraph is contained within this link...
http://www.historynet.com/jackie-robinson
It may be UCLA-related, but I would bet this Pennant is from that event on September 23, 1947. I believe it's more likely that a manufactured pennant like this emanated from a Dodgers Game than a college-related event. Just my opinion...