"Never Been Happier @djohnsonpga," the 24-year-old wrote, posting a snapshot of herself and her new fiance sharing a kiss. Their pose conveniently allowed her diamond sparkler to flash in the pic.
Johnson, 29, also partook in the social-media announcements.
"she said yes!!!" he tweeted, sharing a closeup shot of the enormous rock now adorning Gretzky's finger.
Her brother Trevor also congratulated her on Twitter.
"Congrats to my sister @PaulinaGretzky and @DJohnsonPGA on the engagement. Love you guys," he said.
Gretzy and Johnson have been dating since early 2013, according to Us Weekly. The two made their public debut as a couple in January when she went to Kapalua, Hawaii, for the 2013 PGA Tour, where he won the PGA Tournament of Champions and collected a $1.1-million grand prize, according to Sports Now.
Gretzky's father, the Great One, and her mother, Janet, joined their daughter the following week at the Sony Open in Honolulu. In February, Johnson was partnered with his future father-in-law at the Pebble Beach National Pro-Am in Monterey.
Talk about family bonding time!
Follow Ministry of Gossip @LATcelebs.