One of the standouts from Sunday's Detroit Lions practice was cornerback Jacob Lacey. He had been working primarily on the second string during the first two days of training camp, but he got reps with the first-team defense on Sunday. He made his stay on the first string worthwhile by putting together an outstanding practice.

Jacob Lacey having very good day. Recovered fumble, several breakups. He needed it. Didn't have the best start to camp

— Lions RapidReports (@CBSSportsNFLDET) July 29, 2012

#Lions CB Jacob Lacey with an INT in practice

— Anwar Richardson (@AnwarRichardson) July 29, 2012

#Lions WR Nate Burleson fumbles after reception and Jacob Lacey recovers

— Anwar Richardson (@AnwarRichardson) July 29, 2012

Jacob Lacey having a good cover session in 7on7

— Chris McCosky (@cmccosky) July 29, 2012

Another breakup by #Lions CB Jacob Lacey. Strong day for him

— Anwar Richardson (@AnwarRichardson) July 29, 2012

WR/DB one-on-one drills always bring out the ooohs and aaahs. Jacob Lacey made nice pick to finish segment of practice. #Lions

— Tom Leyden (@TomLeyden) July 29, 2012

Alphonso Smith made a strong case to be one of the starting cornerbacks on Friday and Saturday, but Lacey made a strong case of his own on Sunday. Right now, it looks like that second starting job will come down to Smith and Lacey. This battle will continue throughout training camp and into the preseason, and it should be a good one to watch based on the last few days.

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